Skip to main content

Linux EUVDEUVD-2026-86932

| CVE-2026-98101
2026-09-25 Linux GHSA-wv36-qwc6-r8c9
View
Monitor Track and reassess. Why: No CVSS yet + weak signal (CWE or non-zero EPSS).
Patch available 0.2% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisCVE.org

In the Linux kernel, the following vulnerability has been resolved:

ipv6: mcast: use copy-on-write RCU updates in ip6_mc_source()

pmc->sflist is read locklessly under rcu_read_lock() by inet6_mc_check() during packet reception in the UDP and RAW multicast receive paths.

ip6_mc_source() mutated psl->sl_addr and psl->sl_count in-place when adding or removing a source filter. Additionally, when expanding the filter buffer, newpsl was published via rcu_assign_pointer() before writing the new source into the array.

Because 16-byte struct in6_addr writes are not atomic and array shifting is not synchronized with RCU readers, concurrent readers in inet6_mc_check() could read torn IPv6 addresses or observe duplicated/missed source entries.

Fix this by switching ip6_mc_source() to copy-on-write RCU updates: allocate and fully populate newpsl before publishing it via rcu_assign_pointer(), and reclaim the old filter via kfree_rcu(), matching ip6_mc_msfilter().

Also remove the now unused IP6_SFBLOCK macro.

Affected VersionsENISA

Linux 5.13
Linux 882ba1f73c06831f2a21044ebd8864c485ac04f2 <2c2091e2ee93049fc513ad1e6c99d8b6c809f467
Linux 882ba1f73c06831f2a21044ebd8864c485ac04f2 <c073d1b070f171d206b19c98d71739a97f15b3f1
Linux patch: 7.2.7
Linux 882ba1f73c06831f2a21044ebd8864c485ac04f2 <20db91a052332ef5552bd2f651ffb9db911cf67b
Linux patch: 7.3-rc2
Linux patch: 0
Linux 47c75e3923c8d562fea8daf0ccf31546a7bef0ea
Linux 5.10.261 <5.11
Linux patch: 6.18.53

Affected Packages

euvd linux fix: 5.11

Source: OSV (Open Source Vulnerabilities)

Affects your stack

Affects 1 package in euvd

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Know when the next one hits your stack

  • Watch products and get an email when something new is published
  • Check this CVE against your own stack and servers
  • Exploit and PoC references, threat intelligence from 22 sources

No credit card · 7-day full trial

Lifecycle Timeline

2
Patch available
Sep 25, 2026 - 12:02 EUVD
CVE Published
Sep 25, 2026 - 10:35 cve.org
UNKNOWN (no severity yet)

Threat Intelligence Overview

EPSS Score
0.2%
Top 95% exploitable
Data Quality
3 sources
Confidence: Low

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity Not scored yet
CISA KEV No
Public POC No
EPSS 0.2%
Patch available Yes
Active threat No
Deciding rule
No CVSS yet + weak signal (CWE or non-zero EPSS)
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

Attack Technique

Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy