CVE-2026-83525: Apache Kafka: Incorrect boolean operator in FetchSnapshot RPC handler allows authenticated network clients to crash the KRaft controller via a malformed request
CVE-2026-83525 key facts
- CISA KEV
- Not listed (catalogue checked )
- Highest advisory rating
- Medium
- CVSS base score
- 4.9 (Red Hat)
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H· base score 6.5, scored by CISA-ADPAttack vector: network. Attack complexity: low. Privileges required: low. User interaction: none. Scope: unchanged. Confidentiality impact: none. Integrity impact: none. Availability impact: high.- Weakness
- CWE-480 Use of incorrect operator
- CISA SSVC
- Exploitation: none observed. Automatable: no. Technical impact: partial. CISA, .
- Fixed releases
- Apache: 4.2.2, 4.3.2
- Red Hat: 4.2.2, 4.3.2, 4.4.0
- Assigned by
- apache (CNA)
- CVE record published
- Listed by VulniPulse
- Record changed
Ratings, versions and fixes are quoted from the vendor advisories that cover only CVE-2026-83525; each belongs to its advisory, not to every product listed. How records are collected and checked.
Description
Incorrect operator (CWE-480) in the FetchSnapshot RPC handler in Apache Kafka from 2.8.0 before 4.2.2, and from 4.3.0 before 4.3.2 on all platforms allows an authenticated attacker with CLUSTER_ACTION privilege to cause a denial of service (controller process termination) via a crafted FetchSnapshotRequest with an empty topics array or a topic with no partitions. Users are recommended to upgrade to version 4.2.2, 4.3.2, or 4.4.0, which fix this issue. Users on unsupported branches (4.1.x and earlier) should upgrade to 4.2.2 or later.
Text from the CVE.org record (apache).
How do I fix CVE-2026-83525?
Upgrade to a fixed release named by the vendor:
- Apache: 4.2.2, 4.3.2
- Red Hat: 4.2.2, 4.3.2, 4.4.0
- Users are recommended to upgrade to version 4.2.2, 4.3.2, or 4.4.0, which fix this issue. (Apache)
- Users on unsupported branches (4.1.x and earlier) should upgrade to 4.2.2 or later. (Apache)
Vendor advisories for CVE-2026-83525
Apache
1 advisory- Advisory severityUnrated
Advisory [CVE-2026-83525] Apache Kafka: Incorrect boolean operator in FetchSnapshot RPC handler allows authenticated network clients to crash the KRaft controller via a malformed request.
CVE-2026-83525Source published Source updated
Incorrect operator (CWE-480) in the FetchSnapshot RPC handler in Apache Kafka from 2.8.0 before 4.2.2, and from 4.3.0 before 4.3.2 on all platforms allows an authenticated attacker with CLUSTER_ACTION privilege to cause a denial of service (controller process termination) via a crafted FetchSnapshotRequest with an empty topics array or a topic with no partitions. Users are recommended to upgrade to version 4.2.2, 4.3.2, or 4.4.0, which fix this issue. Users on unsupported branches (4.1.x and earlier) should upgrade to 4.2.2 or later.
- Affected products in this advisory
- Apache Kafka
- Source-reported affected versions
- Apache Kafka 2.8.0 before 4.2.2
- Apache Kafka 4.3.0 before 4.3.2
- Source-reported fixed versions
- 4.2.2
- 4.3.2
- Mitigation guidance
- Users are recommended to upgrade to version 4.2.2, 4.3.2, or 4.4.0, which fix this issue.
- Users on unsupported branches (4.1.x and earlier) should upgrade to 4.2.2 or later.
Red Hat
1 advisory- Advisory severityMedium4.9
Medium [CVE-2026-83525] Denial of Service via crafted FetchSnapshot request
CVE-2026-83525Source published Source updated
Denial of Service via crafted FetchSnapshot request. Red Hat rates this moderate (CVSS 4.9). Weakness: CWE-248.
- Related products — impact not confirmed
- No product details extracted. Check the source bulletin.
- Source-reported affected versions
- < 2.8.0
- < 4.2.2
- < 4.3.0
- < 4.3.2
- Source-reported fixed versions
- 4.2.2
- 4.3.2
- 4.4.0
- Mitigation guidance
- No mitigation guidance extracted; consult the source.
References
- CVE-2026-83525 recordCVE.org
- CVE-2026-83525 detailNVD
- github.com/apache/kafka/pull/23185patch
- kafka.apache.org/cve-listvendor-advisory
Timeline
- CVE record published
- First vendor advisory listed by VulniPulse
- CVE record last updated
More Apache advisories
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