CVE-2026-64543: Linux kernel · tipc: fix use-after-free of the discoverer in tipc_disc_rcv()
Source GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in f05b3f4c78370469286879c765f5a1dd39dbcd32 : patch Linux kernel soon.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 2% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in f05b3f4c78370469286879c765f5a1dd39dbcd32, ec7d54d8cc1723921d671e3272b427c96366506f, b65289e1c3f352a9f92c6e19713ddd647e033253 +5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 27 Jul 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
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AI-suggested
The vulnerability has been resolved in the Linux kernel source by changing the freeing mechanism to use RCU callbacks and adding synchronization barriers on module unload. Users should monitor official Linux kernel advisories and apply updates when available. No generic mitigations are specified by the vendor advisory.
Description
A use-after-free vulnerability in the Linux kernel's TIPC (Transparent Inter-Process Communication) UDP bearer was resolved. The issue occurs because the discoverer object is freed without proper synchronization, leading to a use-after-free condition in tipc_disc_rcv() during UDP packet processing. This vulnerability is reachable from an unprivileged user namespace when TIPC and UDP media support are enabled. The fix involves freeing the discoverer object using an RCU callback and ensuring all callbacks complete before module unload.
References
- nvd.nist.gov/vuln/detail/CVE-2026-64543 (opens in a new tab)
- git.kernel.org/stable/c/1579342d71133da7f00daa02c75cebec7372097b (opens in a new tab)
- git.kernel.org/stable/c/5e215bf1c47fdddf8203a0fe80a0ed594065f101 (opens in a new tab)
- git.kernel.org/stable/c/a0c5fdeb5fa257f8c6d469af266bc087cb5de6a2 (opens in a new tab)
- git.kernel.org/stable/c/b65289e1c3f352a9f92c6e19713ddd647e033253 (opens in a new tab)
- git.kernel.org/stable/c/ec7d54d8cc1723921d671e3272b427c96366506f (opens in a new tab)
- git.kernel.org/stable/c/380413cdfd29fb9fa486c82889132b680c4983c5 (opens in a new tab)
- git.kernel.org/stable/c/4da2ac7749411971e1b222b992da5a172ce45f98 (opens in a new tab)
- git.kernel.org/stable/c/f05b3f4c78370469286879c765f5a1dd39dbcd32 (opens in a new tab)