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Red Hat Linux RHEL & SELinux Vulnerabilities & Security Advisories

1641 advisories tracked · Red Hat Security Data API · 2 listed in the CISA Known Exploited Vulnerabilities catalog

Every row below is a published Red Hat Linux advisory that VulniPulse classified as RHEL & SELinux, with the CVEs, affected and fixed releases and exploitation status the vendor stated. Severity mix: 35 critical, 621 high, 814 medium, 169 low.

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Red Hat Enterprise Linux errata (RHSA) via the official Red Hat Security Data API — CVE severity, CVSS and affected packages. A credential-free official source.

Latest Red Hat RHEL & SELinux advisories

High7.6Red Hat

High [CVE-2026-80186] Stack Overflow in name2utf8 causes DoS and potential code execution

A stack-based buffer overflow vulnerability exists in BlueZ, the Linux Bluetooth protocol stack. A remote user within Bluetooth radio range can send a specially crafted Extended Inquiry Response (EIR) packet that causes a buffer overflow when the target device performs Bluetooth discovery. This vulnerability can lead to a Denial of Service (DoS) by crashing the bluetoothd service and may allow for arbitrary code execution. Red Hat severity: Important — CVSS 7.6 (CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H). Weakness: CWE-120. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 7; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9. Red Hat does not currently list a fixing RHSA for this CVE. Affected products named by the advisory: Red Hat package: bluez.

CVE-2026-80186
Red Hat Enterprise Linux
Aug 25, 2026
High7.1Red Hat

High [CVE-2026-68515] Heap out-of-bounds write in exrmultiview via crafted EXR files

OpenEXR is the reference implementation and specification for the EXR image format, widely used in the motion picture industry. In versions before 3.2.11, 3.3.0 through 3.3.12, and 3.4.0 through 3.4.13, exrmultiview can write past a heap allocation when it combines two attacker-supplied, individually valid scanline EXR files whose union dataWindow is not aligned to one view's channel subsampling. The utility allocates sampled channel storage using a truncated union_width / xSampling, then reads the sampled input through a Slice based on the misaligned union window, producing a heap out-of-bounds write. The trigger is normal public-tool processing, such as exrmultiview left A.exr right B.exr out.exr with crafted but valid inputs, so this is not solely an API or caller-precondition issue. This issue is fixed in versions 3.2.11, 3.3.13, and 3.4.14. A flaw was found in OpenEXR. A remote attacker could exploit this vulnerability by providing specially crafted EXR image files to the exrmultiview utility. When processing these files, the utility can write beyond its allocated memory on the heap, leading to a heap out-of-bounds write. This could allow an attacker to achieve arbitrary code execution or cause a denial of service (DoS) on the affected system. Exploitation requires a local attacker to persuade a user to process specially crafted EXR image files.

CVE-2026-68515
Red Hat Enterprise Linux
Aug 25, 2026
High7.8Red Hat

High [CVE-2026-79992] local shell command injection through the user field in emacs tramp

A flaw was found in Emacs TRAMP. A local attacker could exploit this vulnerability by processing maliciously crafted filenames. This occurs because TRAMP concatenates login arguments without proper sanitization, which are then passed to a local shell. Successful exploitation could lead to arbitrary code execution. This issue requires user interaction with a malicious file, limiting its remote exploitability. Red Hat severity: Important — CVSS 7.8 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H). Weakness: CWE-78. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 7; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9. Will not fix / out of support: Red Hat Enterprise Linux 6. Red Hat does not currently list a fixing RHSA for this CVE. Affected products named by the advisory: Red Hat package: emacs.

CVE-2026-79992
Red Hat Enterprise Linux
Aug 25, 2026
High7.5Vendor: LowRed Hat

High [CVE-2026-63075] QUIC ACK-only packet retention can cause memory exhaustion

Issue summary: When OpenSSL processes QUIC traffic from a peer that repeatedly sends ack-eliciting packets while not acknowledging ACK-only responses, the QUIC stack can retain ACK-only packet metadata for the lifetime of the connection. Impact summary: A remote peer that can complete a QUIC handshake can cause connection-scoped memory growth which may lead to Denial of Service through memory exhaustion, especially with sustained traffic or many concurrent QUIC connections. CWE: CWE-770: Allocation of Resources Without Limits or Throttling Description: When the OpenSSL QUIC stack sends an ACK-only packet, there is no requirement by the QUIC protocol that the peer will acknowledge that ACK-only packet (i.e. it is itself not ack-eliciting). However, the OpenSSL implementation stores the metadata about the ACK frames regardless. In and of itself that's ok, but if a malicious peer establishes a connection, and then drives the connection such that ACK-only packets are forced from the OpenSSL implementation peer (i.e., by sending numerous PING frames), and then withholding any subsequent acks for ack-eliciting data, like legitimate data, said malicious peer can force inappropriate memory growth on the OpenSSL peer, potentially leading to a Denial of Service.

CVE-2026-63075
Red Hat Enterprise Linux
Aug 25, 2026
High7.8Red Hat

High [CVE-2026-79655] path traversal in sos clean tar extraction via unvalidated symlink/hardlink targets leads to arbitrary file write

A flaw was found in sos clean, a utility within the sos package. This vulnerability allows a local attacker to perform arbitrary file creation or overwrite. By crafting a malicious tar archive, an attacker can exploit a path traversal issue during tar extraction, where symlink and hardlink targets are not properly validated. This enables the attacker to write files to arbitrary locations on the system with the privileges of the sos clean process, which often runs as root. Red Hat severity: Important — CVSS 7.8 (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H). Weakness: CWE-59. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 7; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9. Will not fix / out of support: Red Hat Enterprise Linux 6. Red Hat does not currently list a fixing RHSA for this CVE. Affected products named by the advisory: Red Hat package: sos.

CVE-2026-79655
Red Hat Enterprise Linux
Aug 25, 2026
High7.5Vendor: MediumRed Hat

High [CVE-2026-18798] QUIC server may trigger double free when processing INITIAL packet

Issue summary: QUIC server may double free QRX (QUIC record layer RX) object when channel creation fails for initial packet. Impact summary: Double free leads to heap corruption, which typically results in termination of QUIC server process, leading to Denial of Service. There is so far no evidence that this double free is exploitable for remote code execution, thus it is considered highly improbable. CWE: CWE-415: Double Free Description: In order to validate initial packet, OpenSSL QUIC stack default packet handler (port_default_packet_handler()) creates a so-called QRX object. If the initial packet validates successfully with QRX object, the default packet handler proceeds to channel (connection object) creation. The QRX object used for packet validation is passed to port_bind_channel(), so it becomes part of the newly created connection. If port_bind_channel() fails, then it also frees the QRX object. Once port_bind_channel() returns, the port_default_packet_handler() detects the failure and proceeds to the error branch, where the same QRX object is freed for the second time. The failure in port_bind_channel() function can be induced with a relatively low effort by a malformed (non RFC 9000 compliant) INITIAL packet.

CVE-2026-18798
Red Hat Enterprise Linux
Aug 25, 2026
High7.5Vendor: MediumRed Hat

High [CVE-2026-63072] heap buffer overflow in CMS key unwrapping

Issue summary: OpenSSL CMS decryption sizes the key-unwrap output buffer based on querying the unwrapped key size, but the AES-WRAP-PAD unwrap primitive can write and cleanse more bytes than that query reports, causing an 8-byte out-of-bounds heap write. Impact summary: An attacker who supplies a crafted CMS message can trigger a deterministic 8-byte out-of-bounds heap write when the victim decrypts it with CMS_decrypt(), corrupting the heap and typically resulting in a Denial of Service. CWE: CWE-787: Out-of-bounds Write Description: The key-wrap OID is potentially attacker-controlled on the wire. CMS unwrapping allows both id-aesNNN-wrap-pad and id-aesNNN-wrap ciphers. An attacker can take a legitimate message and change a single OID byte to select the padded variant while leaving the message otherwise valid. Since the unwrap key is derived from the recipient's private operation (ECDH key agreement or ML-KEM decapsulation), the RFC 5649 integrity check cannot pass, and the decryption fails with integrity failure. The write is a fixed-size (8-byte), fixed-value (zero) heap overflow immediately past the allocation, requires no special configuration, and is reachable from the public CMS_decrypt() function. The consequence is a heap corruption leading to a Denial of Service.

CVE-2026-63072
Red Hat Enterprise Linux
Aug 25, 2026
High7.5Vendor: MediumRed Hat

High [CVE-2026-63076] invalid pointer dereference in CMP server via crafted protectionAlg

Issue summary: OpenSSL CMP password based protection verification only checks whether the protectionAlg parameter was not NULL and not its ASN.1 type, before treating it as a PBMParameter. A crafted message can contain a parameter of a different type, which is then dereferenced as an invalid pointer. Impact summary: A remote, unauthenticated attacker can crash an application acting as a CMP server that accepts PBM-protected messages, or a CMP client talking to a malicious or intercepted CMP server, resulting in a Denial of Service. CWE: CWE-476: NULL Pointer Dereference Description: When verifying the password-based MAC protection of a CMP message, OpenSSL library reads the protectionAlg algorithm parameter with X509_ALGOR_get0(), which returns both the parameter type and its value pointer. The value is then cast to an ASN1_STRING and treated as the expected PBMParameter after only checking that pointer is not NULL. The parameter type returned by X509_ALGOR_get0() was never consulted. This happens during protection verification, before any MAC is computed, so no knowledge of the PBM shared secret is required; the only precondition is that PBM verification is reachable. Affected products named by the advisory: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 9; Cert Manager support for Red Hat OpenShift release 1.20; Red Hat Hardened Images; and 10 more.

CVE-2026-63076
Red Hat Enterprise Linux
Aug 25, 2026
High7.5Vendor: LowRed Hat

High [CVE-2026-14457] RPK server signature algorithm selection can dereference a missing certificate

Issue summary: In a server or client configuration with RFC7250 Raw Public Keys (RPKs) enabled, and only the private key (with no associated certificate) configured locally, a NULL pointer dereference may occur when the remote peer solicits raw public keys and also sends the typically omitted "signature_algorithms_cert" TLS extension. Impact summary: The impact is limited to a possible Denial of Service as a result of an application abort, no data disclosure or remote command execution are possible. CWE: CWE-476: NULL Pointer Dereference Description: While a passing comment in sample code in the documentation suggests that key-only RPK configurations are supported, the best-practice RPK configuration is to always configure a corresponding certificate (possibly self-signed or signed by any convenient CA). When the private key is configured along with a matching certificate, the "signature_algorithms_cert" extension is handled reliably even without the fix, and peer clients or servers that don't support raw public keys may be able to complete a TLS connection by pinning or verifying the corresponding certificate or its public key. Deployments that prefer to configure just a private key with no certificate need to upgrade to an updated release as noted below.

CVE-2026-14457
Red Hat Enterprise Linux
Aug 25, 2026
High7.5Vendor: LowRed Hat

High [CVE-2026-54874] excessive memory use buffering DTLS records for a future epoch

Issue summary: Receiving a DTLS record for a future epoch while a handshake is in progress causes OpenSSL to buffer far more memory than the record itself requires. Impact summary: A peer can use a small amount of network traffic to make an OpenSSL DTLS endpoint retain a disproportionately large amount of memory, which may lead to a Denial of Service. CWE: CWE-405: Asymmetric Resource Consumption (Amplification) Description: While a DTLS handshake is in progress, a peer may legitimately have already moved on to the next epoch (for example, having sent its ChangeCipherSpec and Finished messages) before the local endpoint has processed the same transition, typically because of reordering on the underlying UDP transport. OpenSSL buffers such early records so that they can be processed once the local endpoint catches up. Buffering a record currently retains the entire read buffer it arrived in, which is sized to hold the largest possible DTLS record (around 16 kilobytes), rather than just the bytes that make up the record itself. Up to 100 such records may be buffered per connection. As a result, a peer that sends a stream of small forged records claiming to belong to the next epoch can cause an OpenSSL DTLS endpoint to retain around 1.7 megabytes of memory, despite sending only a small fraction of that amount of data over the network.

CVE-2026-54874
Red Hat Enterprise Linux
Aug 25, 2026
High7.5Vendor: LowRed Hat

High [CVE-2026-63074] CMP indefinite cache growth of ExtraCerts

Issue summary: The OpenSSL Certificate Management Protocol (CMP) caches additional certificates (extraCerts) sent in a CMP message, but never expunges them (for instance if they are invalid). If a server reuses an OSSL_CMP_CTX frequently, this cache of extraCerts may grow unboundedly, and a malicious client may flood a CMP server with requests driving this growth. Impact summary: Users utilizing a CMP server that reuses a single OSSL_CMP_CTX for the lifetime of a server process may observe unbounded memory growth in the event a malicious client repeatedly sends requests containing unique extra certificates, which may lead to OOM conditions. CWE: CWE-770: Allocation of Resources Without Limits or Throttling Description: If a remote user sends CMP messages to a server with a list of extraCerts and the message is rejected, the extraCerts from the message remains in the server contexts untrusted certificate stack. This exposes servers with long lived ctx objects to Denial of Service attacks in which an attacker sends messages intending to be rejected with a large list of additional certificates repeatedly, forcing the server to store them indefinitely. The issue was fixed by removing the added extra certs if the message is rejected, using the same method as when the context is configured to not do caching at all.

CVE-2026-63074
Red Hat Enterprise Linux
Aug 25, 2026
High7.3Red Hat

High [CVE-2026-52491] Arbitrary code execution via thumbnail.c: main component

An issue in libtiff 85f2ac8e0b01cb7db2bbecf4a3b891bdbef67938 allows an attacker to execute arbitrary code via the libtiff/tools/thumbnail.c: main() component A flaw was found in libtiff. An attacker could exploit this vulnerability by processing a specially crafted file, leading to arbitrary code execution. Successful exploitation could allow the attacker to take control of the affected system. Red Hat severity: Important — CVSS 7.3 (CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H). Weakness: CWE-120. Affected Red Hat products: Red Hat Hardened Images; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 7. Red Hat lists Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 7; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9 as not affected. Will not fix / out of support: Red Hat Enterprise Linux 6. Red Hat fixing advisory: RHSA-2026:53467. Affected products named by the advisory: Red Hat package: libtiff.

CVE-2026-52491
Red Hat Enterprise Linux
Aug 25, 2026
High7.0Red Hat

High [CVE-2026-78465] Gimp: integer overflow in pcx loader (planes=4) leads to heap overflow on 32-bit

A flaw was found in the file-pcx plugin in GIMP, affecting 32-bit builds only. When processing a PCX image file, the plugin calculates memory allocation sizes based on the image dimensions and the number of color planes. If a crafted file sets the number of planes to 4 alongside sufficiently large dimensions, the calculation exceeds the 32-bit integer limit and overflows, resulting in an undersized heap-based buffer allocation. This integer overflow issue results in a heap-based buffer overflow when the plugin subsequently writes image data into the undersized buffer, causing memory corruption, potentially leading to arbitrary code execution or a denial of service. To exploit this vulnerability, an attacker needs to convince a user to process a specially crafted PCX image with GIMP, reducing the likelihood of exploitation. However, successful exploitation may potentially lead to arbitrary code execution or a denial of service. Default Red Hat Enterprise Linux security features, including SELinux enforcement, Address Space Layout Randomization (ASLR) and NX (No-Execute) stack protection, significantly increase the difficulty of achieving arbitrary code execution, limiting the impact of this vulnerability. Due to this reason, this flaw has been rated with an important severity. Red Hat severity: Important — CVSS 7 (CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H).

CVE-2026-78465
Red Hat Enterprise Linux
Aug 24, 2026
High7.1Red Hat

High [CVE-2025-9615 +1] 802-1x ca-path and phase2-ca-path bypass private_user restriction, allowing WPA-Enterprise server validation bypass (incomplete fix for CVE-2025-9615)

NetworkManager did not apply the private_user restriction to the 802-1x.ca-path and phase2-ca-path directory-valued connection properties. This incomplete fix for CVE-2025-9615 allows an unprivileged local user to point a private WPA-Enterprise (802.1X) connection profile's CA path at an attacker-controlled directory, bypassing server certificate validation and enabling credential theft via a rogue access point. This issue is limited to WPA-Enterprise (802.1X) network connections; open and WPA2-Personal (PSK) networks are not affected. Exploitation requires an unprivileged, active local user session holding the (commonly passwordless on desktop systems) settings.modify.own polkit permission; the flaw is not reachable from a remote or inactive SSH session. NetworkManager is the sole affected component: wpa_supplicant/hostapd are downstream consumers that correctly use whatever ca_path directory they are handed and require no change. Red Hat severity: Important — CVSS 7.1 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N). Weakness: CWE-863. Affected Red Hat products: Red Hat Enterprise Linux 10. Red Hat does not currently list a fixing RHSA for this CVE. Affected products named by the advisory: Red Hat package: networkmanager.

CVE-2025-9615CVE-2026-19685
Red Hat Enterprise Linux
Aug 24, 2026
High7.0Vendor: MediumRed Hat

High [CVE-2026-78367] rpmbuild getTarSpec crafted tar member name → macro injection

A vulnerability was found in RPM's rpmbuild tarball processing. When processing a crafted source archive, the getTarSpec() function in tools/rpmbuild.cc passes an attacker-controlled tar archive member name to rpmExpand() as part of a %{basename:...} macro expression. A specially crafted.spec member name can therefore inject RPM macros, including Lua expressions, resulting in arbitrary code execution with the privileges of the user running rpmbuild. This can be exploited when a victim or automated build system processes an attacker-controlled source tarball using rpmbuild tarball mode (such as -ts, -ta, or -tb). This issue is considered Moderate severity because, although successful exploitation can result in arbitrary code execution with the privileges of the rpmbuild process, exploitation requires an attacker to supply a specially crafted source tarball and have it processed by rpmbuild in tarball mode. The vulnerable code is not exposed as a network service and cannot be directly triggered remotely without this archive-processing workflow. Red Hat severity: Moderate — CVSS 7 (CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H). Weakness: CWE-94. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 7; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9; Red Hat Hardened Images.

CVE-2026-78367
Red Hat Enterprise Linux
Aug 24, 2026
High8.8Red Hat

High [CVE-2026-78376] use-after-free of JSCValue function parameters

A flaw was found in WebKitGTK. Processing malicious web content can cause a use-after-free issue due to improper memory handling and result in memory corruption. To exploit this issue, an attacker needs to trick a user into processing or loading malicious web content. Due to this reason, this flaw has been rated with an important severity. Additionally, this issue can cause memory corruption and the possibility of remote code execution is not discarded. Red Hat severity: Important — CVSS 8.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H). Weakness: CWE-416. Affected Red Hat products: Red Hat Enterprise Linux 9; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 7; Red Hat Enterprise Linux 8. Will not fix / out of support: Red Hat Enterprise Linux 6. Red Hat fixing advisory: RHSA-2026:69098. Affected products named by the advisory: Red Hat package: webkit2gtk3; Red Hat package: webkitgtk4.

CVE-2026-78376
Red Hat Enterprise Linux
Aug 24, 2026
High7.5Red Hat

High [CVE-2026-76172] URI parsing flaw enables server-side request forgery and redirects

fast-uri is a URI parser for Node.js. During parsing it runs a legacy decoding pass over the scheme component and never re-escapes the result, and serialization writes the scheme back out verbatim, unlike the host component which is re-escaped. As a result an input whose scheme carries percent-encoded slashes parses as a scheme with no authority, so the parsed host and error are both undefined, yet resolving or normalizing that same input emits a network-path reference whose authority is attacker-chosen and re-parses to that host. An application that allowlists on the parsed host, or treats a reference with no authority as safe to resolve against its base, gets the opposite of what it checked, giving an off-site redirect, server-side request forgery, or address-policy bypass. The legacy decoder also expands non-standard escape forms, widening the issue past upstream filters, and control characters in the scheme can reach the output as raw carriage return and line feed. The affected versions are 2.3.1 up to but not including 2.4.5, 3.0.0 up to but not including 3.1.6, and 4.0.0 up to but not including 4.1.3. The issue is fixed in 2.4.5, 3.1.6, and 4.1.3, which reject a scheme that is not valid after decoding. Users should upgrade to a patched version.

CVE-2026-76172
Red Hat Enterprise Linux
Aug 24, 2026
High7.5Red Hat

High [CVE-2026-75975] Server-side request forgery via malformed IPv6 normalization

fast-uri is a URI parser for Node.js. Its custom parser for bracketed IPv6 literals does not validate the complete IPv6 grammar, so invalid trailing text in an authority can be silently discarded and a malformed attacker-controlled host is turned into a different valid IPv6 destination. For example, a bracketed literal with invalid trailing characters is normalized to the unspecified address, which a Node HTTP client then connects to a local service over loopback, and other malformed literals collapse to private-range addresses. No error is set on the parsed result, so an application checking the error field cannot detect the rewrite. An application that normalizes untrusted URLs before outbound requests, redirects, proxy routing, or address-policy enforcement can be redirected to a local or private IPv6 target, giving a server-side request forgery and address-policy bypass primitive. The affected versions are 2.3.1 up to but not including 2.4.5, 3.0.0 up to but not including 3.1.6, and 4.0.0 up to but not including 4.1.3. Users should upgrade to a patched version. The parser's incomplete validation of bracketed IPv6 literals allows attackers to inject malformed authority components that are silently normalized to different valid IPv6 destinations.

CVE-2026-75975
Red Hat Enterprise Linux
Aug 24, 2026
High7.5Red Hat

High [CVE-2026-75899] Server-Side Request Forgery via repeated hostname percent-decoding

fast-uri is a URI parser for Node.js. It decodes percent escapes in a hostname during parsing and then decodes the parsed hostname a second time during authority recomposition, so a single call to normalize or resolve can turn nested percent-encoded input into a different network destination such as a loopback hostname or address. For example, a doubly encoded host that spells out a loopback name decodes to that live host in one operation, which contradicts RFC 3986 section 2.4 that an implementation must not decode the same string more than once. An application that normalizes or resolves an untrusted HTTP-family URI before outbound routing, redirect validation, or a host-policy check can receive a destination different from the one the original encoded host represented, giving a server-side request forgery and host-policy bypass primitive. This is an incomplete-fix variant of CVE-2026-6322. The affected versions are 2.4.1 up to but not including 2.4.5, 3.1.2 up to but not including 3.1.6, and 4.0.0 up to but not including 4.1.3. Users should upgrade to a patched version. This double decoding can allow a remote attacker to manipulate a URI to point to a different network destination, such as a loopback address.

CVE-2026-75899
Red Hat Enterprise Linux
Aug 24, 2026
High7.5Red Hat

High [CVE-2026-75931] Host confusion via skipped IDN canonicalization

fast-uri is a URI parser for Node.js. It canonicalizes a host to its ASCII form only when the input carries an explicit scheme, so a scheme-relative reference such as a host preceded by two slashes is returned with its host verbatim and no error set. An application that extracts a host with fast-uri to check it against a policy list and then resolves the same reference can make its decision on one host while the destination is another, enabling host confusion and policy bypass. The affected versions are 2.4.2 up to but not including 2.4.5, 3.1.3 up to but not including 3.1.6, and 4.0.1 up to but not including 4.1.3. The issue is fixed in 2.4.5, 3.1.6, and 4.1.3, which canonicalize the host consistently across the resolve path. Users should upgrade to a patched version. This vulnerability arises because the parser fails to consistently convert internationalized domain names (IDN) to their standard ASCII form when processing scheme-relative references. This inconsistency can lead to host confusion, where an application might validate a URI against a security policy using one hostname, but then resolve to a different, potentially malicious, hostname. This discrepancy could allow an attacker to bypass security policies and access unauthorized resources. Red Hat severity: Important — CVSS 7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N). Weakness: CWE-444.

CVE-2026-75931
Red Hat Enterprise Linux
Aug 24, 2026

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