CVE-2026-90392: Linux kernel · bpf: Fix potential UAF when reading bpf link info
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 6% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
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 17 Sep 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
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 fix is available that applies RCU protection when accessing link->prog to prevent use-after-free. Users should update to patched Linux kernel versions that include this fix. Since this is a kernel vulnerability, applying official kernel updates from the vendor or distribution is the recommended remediation. No additional mitigations are specified or required beyond applying the official fix.
Description
A use-after-free (UAF) vulnerability in the Linux kernel's BPF subsystem was fixed. The issue occurred because the bpf_link_show_fdinfo and bpf_link_get_info_by_fd functions accessed link->prog without proper locking, allowing a concurrent update to free the old program and cause UAF. The fix involves using RCU protection to safely access link->prog and ensure its lifetime during reads.
References
- nvd.nist.gov/vuln/detail/CVE-2026-90392 (opens in a new tab)
- git.kernel.org/stable/c/79347e42cfbc9e78872922e8f08a70609c9af82f (opens in a new tab)
- git.kernel.org/stable/c/85cf991c881e7198be32be05a9daa2625390c8b3 (opens in a new tab)
- git.kernel.org/stable/c/863f3ddd0b8ac65abfb50d3be0869268ac0e277b (opens in a new tab)
- git.kernel.org/stable/c/a5c936ac904767fc1d943d40b0308bcb2ae2509b (opens in a new tab)
- git.kernel.org/stable/c/d7d7208e2603b45724b684f4df73904fb347741e (opens in a new tab)
- ubuntu.com/security/CVE-2026-90392 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-90392 (opens in a new tab)
- git.kernel.org/linus/863f3ddd0b8ac65abfb50d3be0869268ac0e277b (opens in a new tab)