CVE-2026-97939: Linux kernel · ipmr: account multicast table and route memory
Source GCVE Database
Not known to be exploited · fixed in ec1c6140394ee87127479bc500a3158b125bf07a : update Linux kernel when convenient.
Data as of 30 Oct 2026, 17:19 UTC
Rated Medium by Threat Radar's AI analysis · CVSS not yet scored by NVD
Thin evidence
One scorer or none- Patch
- Available – fixed in ec1c6140394ee87127479bc500a3158b125bf07a, d0a2e2a4ee6bfe51e398bfb6921a7d0f4c26bc1c, b7ee18725f2292ab554aa96a101ae42d45f008bd +5
Exploitation evidence
Disclosed: evidence found.
CVE published 25 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 30 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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AI-suggested
A fix has been implemented in the Linux kernel to properly account mr_table allocations to memory control groups and mark multicast forwarding cache entries accordingly. Users should apply the official kernel updates that include this fix. No additional mitigation steps are indicated.
Description
A vulnerability in the Linux kernel's multicast routing (ipmr) subsystem allowed a netadmin in a user+net namespace to create many multicast routing tables without proper memory accounting. This caused unreclaimable memory growth on the host due to uncharged mr_table allocations. The issue has been resolved by charging mr_table allocations to the memory controller and marking multicast forwarding cache entries accordingly.
References
- nvd.nist.gov/vuln/detail/CVE-2026-97939 (opens in a new tab)
- git.kernel.org/stable/c/0264b3ee09b118fec8a5471b4ca288f8ab84722f (opens in a new tab)
- git.kernel.org/stable/c/20424f267c9dbdfcade28b2b2306767a7dfb43d1 (opens in a new tab)
- git.kernel.org/stable/c/21e0749e8ef272ac7e3eefe0fa488a5983f4b038 (opens in a new tab)
- git.kernel.org/stable/c/3e808d8dfebd8f114a747bd90c8f7d2a6fd7474f (opens in a new tab)
- git.kernel.org/stable/c/57c523e95ea2608a19e6bfcd664d641ddf7bc4b4 (opens in a new tab)
- git.kernel.org/stable/c/b7ee18725f2292ab554aa96a101ae42d45f008bd (opens in a new tab)
- git.kernel.org/stable/c/d0a2e2a4ee6bfe51e398bfb6921a7d0f4c26bc1c (opens in a new tab)
- git.kernel.org/stable/c/ec1c6140394ee87127479bc500a3158b125bf07a (opens in a new tab)