CVE-2026-74289: Linux kernel · ipv4: fib: Don't dump dying fib_info in fib_leaf_notify().
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in 7.0.0-1014.14~24.04.1 : 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 7.0.0-1014.14~24.04.1, 7.0.0-1017.17~24.04.1, 7.0.0-1016.16~24.04.1 +12
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 15 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 |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A patch is available for this vulnerability. Users should apply the official Linux kernel updates for the affected Linux Azure versions as provided by their vendor. The Ubuntu security advisory USN-8888-1 confirms the availability of fixes. No additional mitigation steps are indicated beyond applying the update.
Description
A use-after-free vulnerability in the Linux kernel's IPv4 fib subsystem was resolved. The issue involved unsafe reference counting during fib_info dumping under RCU, potentially leading to memory corruption. This flaw affected specific Linux Azure kernel versions and was addressed by ensuring the lifetime of fib_info in fib_leaf_notify(). The vulnerability has a CVSS score of 7.8, indicating a high impact on confidentiality, integrity, and availability. A patch is available and should be applied to affected versions.
References
- nvd.nist.gov/vuln/detail/CVE-2026-74289 (opens in a new tab)
- git.kernel.org/stable/c/06b693d2eb6651a63ad85bad8673de3b7d4edd6d (opens in a new tab)
- git.kernel.org/stable/c/676482da8d938ea72c26da0fc86af2d2ec238ab2 (opens in a new tab)
- ubuntu.com/security/CVE-2026-74289 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-74289 (opens in a new tab)
- git.kernel.org/linus/06b693d2eb6651a63ad85bad8673de3b7d4edd6d (opens in a new tab)
- git.kernel.org/stable/c/7907a395701b339c2d68f37456d395e953c74795 (opens in a new tab)
- git.kernel.org/stable/c/7980a13add57f97c5da1dc961d0145a6ad2a7f98 (opens in a new tab)
- git.kernel.org/stable/c/8bdb20b8a581495062b5879f4e9d435da648b3b0 (opens in a new tab)
- git.kernel.org/stable/c/bea03e887db5a8a79234531faf14cf2c4d8816c3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8889-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8887-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8886-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8887-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8887-3 (opens in a new tab)