Medium [CVE-2026-56115] Denial of Service via crafted DHCPv6 ADVERTISE message
This medium-severity Red Hat Linux advisory covers CVE-2026-56115 affecting Red Hat Enterprise Linux 10, Red Hat package: dhcpcd.
Aggregated and source-linked by VulniPulse. Data sources, validation and limitations.
VulniPulse record published Record updated
Summary
Bootimus through 0.1.70 contains a broken access control vulnerability that allows authenticated low-privileged users to perform administrative actions by exploiting missing role enforcement in the JWTMiddleware function in internal/auth/auth.go, which validates JWT tokens and account status but fails to inspect the is_admin flag.
Attackers can send requests to any endpoint under the /api/users path to create new administrator accounts or reset administrator passwords, thereby gaining full control of the server and the ability to modify boot menus and installation scripts served to PXE clients. A flaw was found in dhcpcd.
This vulnerability allows an unauthenticated attacker on the same network link to trigger a one-byte stack out-of-bounds write. By sending a specially crafted DHCPv6 ADVERTISE message with an oversized option, the attacker can corrupt adjacent stack memory.
This can lead to a denial of service (DoS) in the affected system. Red Hat severity: Moderate — CVSS 5.3 (CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H).
Weakness: CWE-787. 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: dhcpcd.
Is CVE-2026-56115 exploited?
No exploitation is reported in the sources VulniPulse tracks: CVE-2026-56115 is not in the CISA KEV catalog (checked ) and this advisory does not report exploitation. That is not proof the vulnerability cannot be exploited.
How do I fix CVE-2026-56115?
The advisory VulniPulse tracks names no fixed release. Follow Red Hat's guidance for workarounds and updates.
Confirm against the vendor advisory before you patch.
- 0.1.70
Official advisory · high-confidence parse· fetched 14 days ago·verify at source
Fixed versions
No fixed release is recorded yet. That does not prove no patch exists. Confirm against the vendor advisory.
Official advisory · high-confidence parse· fetched 14 days ago·verify at source
Mitigation
The source record does not include mitigation steps. That does not mean no fix exists. Read the vendor advisory below for the authoritative guidance.
Official advisory · high-confidence parse· fetched 14 days ago·verify at source
Get an email when Red Hat RHEL & SELinux publishes the next one.
See Red Hat RHEL & SELinux's last 90 days of advisories first. Then choose one product with live alerts free for life, or a free month of real-time alerts on everything with the severity, the fixed version and the vendor's link (card needed, then US$15/month; we email you before the first charge).
More Red Hat Linux advisories
- CVE-2026-111497Oct 22, 2026Out-of-Bounds Write in Google Brotli Decoder
- CVE-2026-109619Oct 21, 2026fatal error handling retains stale request state leading to use-after-free
- CVE-2026-109618Oct 21, 2026OOM bailout during request parsing leads to memory corruption and RCE
- CVE-2026-119977Oct 31, 2026Arbitrary code execution via predictable upgrade staging paths
- CVE-2026-97229Oct 13, 2026integer overflow issue in CI/CD regular expression compiler
- CVE-2026-64849Aug 17, 2026Unauthenticated full-read SSRF in webhook delivery: _validate_webhook_url bypassed
iPhone and Android apps · New on the App Store
Monitor future Red Hat Linux CVEs from your phone.
Choose a whole vendor or a precise platform, then receive matching security advisories by phone notification, email, or both. Coverage follows 34 official vendor sources and 160+ reviewed platform categories.
Discussion(0)
No comments yet. Share field notes, upgrade gotchas, or questions — verify against the vendor advisory before acting on community advice.
Sign in to join the discussion.