VulnerabilityPublished 6 Oct 2026Updated 19 Oct 2026

CVE-2026-98289: Linux kernel · af_unix: Unify scc_index when finalising SCC in __unix_walk_scc().

Affects Linux kernelSource CVE Database V5

Not known to be exploited · fixed in be550ee108ad80828aa61280400bedfc7e7c39d3 : update Linux kernel when convenient.

Data as of 26 Oct 2026, 17:16 UTC

Severity

Medium

Rated Medium by Threat Radar's AI analysis · CVSS not yet scored by NVD

EPSS: 0.1% chance of exploitation in 30 days – higher than 5% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in be550ee108ad80828aa61280400bedfc7e7c39d3, b8f71d69380a5fbc734c868acbeb560f1de1766f, 6.7 +2

Exploitation evidence

Disclosed: evidence found.
CVE published 6 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected >=6.1.141 <6.2 >=6.6.93 <6.7	Fixed in be550ee108ad80828aa61280400bedfc7e7c39d3 b8f71d69380a5fbc734c868acbeb560f1de1766f 6.7 6.2 4a4263dfeabad72f95e8ab6e15146861fa4144dd
LinuxLinux	Affected =6.10	Fixed in–

AI-suggested

A fix for this vulnerability has been implemented and is available in Linux kernel versions 6.2, 6.7, and later. Users and administrators should update to these or later kernel versions to remediate the issue. No additional mitigation actions are indicated.

Description

CVE-2026-98289 is a vulnerability in the Linux kernel's af_unix subsystem related to the handling of strongly connected components (SCC) during garbage collection. The issue arises because the scc_index values are not unified across all vertices in an SCC, which can cause the garbage collector to incorrectly assume some vertices belong to different SCCs, preventing proper cleanup. This flaw was fixed by unifying the scc_index when finalizing SCCs in the __unix_walk_scc() function.

Impact

The vulnerability can cause the af_unix subsystem's garbage collector to fail to clean up certain strongly connected components due to inconsistent scc_index values. This may lead to resource leakage within the kernel, potentially affecting system stability or performance. There is no indication of direct exploitation or security breach impact such as privilege escalation or denial of service from the provided data.

Summary

The vulnerability in the Linux kernel af_unix subsystem involves inconsistent scc_index values assigned to vertices within the same strongly connected component (SCC) during the execution of Tarjan's algorithm. Specifically, the unix_vertex_dead() function assumes all vertices in an SCC share the same lowpoint (scc_index), but this assumption fails when an SCC has multiple back edges and the depth-first search (DFS) order varies. This inconsistency can prevent proper garbage collection of SCCs. The fix unifies the scc_index across all vertices in the SCC during finalization in __unix_walk_scc(), ensuring correct garbage collection behavior.

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Oct 2026, 11:53 UTC

Technical details

References

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