CVE-2026-68409: Linux kernel · Use After Free
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 8.8 High · fixed in b679c1cffb2f3d0854b8b05ea9e909ad6489046f : patch Linux kernel soon.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 16% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Total control over the software or total information disclosure
CISA SSVC assessment, 2026-10-16.
- Patch
- Available – fixed in b679c1cffb2f3d0854b8b05ea9e909ad6489046f, aa2eb62525188269cdd402a583b9a8ed94657ff0, a5afc00280986063f1c355821544fabbb2a960f7 +2
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 10 Aug 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.
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– |
Description
In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: defer link RX stats percpu free to RCU sta_remove_link() frees a removed MLO link's RX stats percpu buffer right away, but defers only the link container to RCU: sta_info_free_link(&alloc->info); kfree_rcu(alloc, rcu_head); The RX fast path reads link_sta under rcu_read_lock and writes the percpu stats. A reader that resolved link_sta before the removal keeps the pointer. The container stays alive from the kfree_rcu, so the read still works. But the percpu block it points to is already freed. This needs uses_rss. That is when pcpu_rx_stats exists. The full STA teardown frees the deflink stats only after synchronize_net(). The link removal path had no such barrier. The race is hard to win in practice, but the free should still wait for RCU. Free the link together with its data from a single RCU callback, so the percpu block is reclaimed only after readers drain.
References
- git.kernel.org/stable/c/a5afc00280986063f1c355821544fabbb2a960f7 (opens in a new tab)
- git.kernel.org/stable/c/b679c1cffb2f3d0854b8b05ea9e909ad6489046f (opens in a new tab)
- git.kernel.org/stable/c/2aa1789880fa5e41049b0f6a74a4fc2fa1997610 (opens in a new tab)
- git.kernel.org/stable/c/a03fceae0c65b31ce31840dac5e26684ceecb65b (opens in a new tab)
- git.kernel.org/stable/c/aa2eb62525188269cdd402a583b9a8ed94657ff0 (opens in a new tab)