CVE-2025-38273: Linux kernel · net: tipc: fix refcount warning in tipc_aead_encrypt
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in 5.15.0-1092.99~20.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.15.0-1092.99~20.04.1, 5.15.0-1096.105~20.04.1, 5.15.0-1092.101~20.04.1 +26
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 10 Jul 2025
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.
Patches and advisories
- ubuntu.com/security/notices/USN-7774-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7775-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7776-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7775-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7775-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-5 (opens in a new tab)
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 24.04 LTSlinux-azure-6.11pkg:deb/ubuntu/linux-azure-6.11?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-gcp-6.11pkg:deb/ubuntu/linux-gcp-6.11?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-hwe-6.11pkg:deb/ubuntu/linux-hwe-6.11?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-lowlatency-hwe-6.11pkg:deb/ubuntu/linux-lowlatency-hwe-6.11?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-raspi-realtimepkg:deb/ubuntu/linux-raspi-realtime?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-realtimepkg:deb/ubuntu/linux-realtime?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
In the Linux kernel, the following vulnerability has been resolved: net: tipc: fix refcount warning in tipc_aead_encrypt syzbot reported a refcount warning [1] caused by calling get_net() on a network namespace that is being destroyed (refcount=0). This happens when a TIPC discovery timer fires during network namespace cleanup. The recently added get_net() call in commit e279024617134 ("net/tipc: fix slab-use-after-free Read in tipc_aead_encrypt_done") attempts to hold a reference to the network namespace. However, if the namespace is already being destroyed, its refcount might be zero, leading to the use-after-free warning. Replace get_net() with maybe_get_net(), which safely checks if the refcount is non-zero before incrementing it. If the namespace is being destroyed, return -ENODEV early, after releasing the bearer reference. [1]: https://lore.kernel.org/all/68342b55.a70a0220.253bc2.0091.GAE@google.com/T/#m12019cf9ae77e1954f666914640efa36d52704a2
References
- ubuntu.com/security/CVE-2025-38273 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-38273 (opens in a new tab)
- git.kernel.org/linus/f29ccaa07cf3d35990f4d25028cc55470d29372b (opens in a new tab)
- git.kernel.org/stable/c/307391e8fe70401a6d39ecc9978e13c2c0cdf81f (opens in a new tab)
- git.kernel.org/stable/c/445d59025d76d0638b03110f8791d5b89ed5162d (opens in a new tab)
- git.kernel.org/stable/c/9ff60e0d9974dccf24e89bcd3ee7933e538d929f (opens in a new tab)
- git.kernel.org/stable/c/acab7ca5ff19889b80a8ee7dec220ee1a96dede9 (opens in a new tab)
- git.kernel.org/stable/c/c762fc79d710d676b793f9d98b1414efe6eb51e6 (opens in a new tab)
- git.kernel.org/stable/c/e0b11227c4e8eb4bdf1b86aa8f0f3abb24e0f029 (opens in a new tab)
- git.kernel.org/stable/c/f29ccaa07cf3d35990f4d25028cc55470d29372b (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7775-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7776-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7775-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7775-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-5 (opens in a new tab)