CVE-2026-22977: Linux kernel · net: sock: fix hardened usercopy panic in sock_recv_errqueue
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.5 Medium · fixed in 5.15.0-1103.110~20.04.1 : update Linux kernel when convenient.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 8% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.15.0-1103.110~20.04.1, 5.15.0-1110.119~20.04.1, 5.15.0-1103.112~20.04.1 +57
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 21 Jan 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 25.10linuxpkg:deb/ubuntu/linux@6.17.0-40.40?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws@6.17.0-1019.19?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure@6.17.0-1020.20?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde@6.17.0-1017.17?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-gcppkg:deb/ubuntu/linux-gcp@6.17.0-1020.22?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-oraclepkg:deb/ubuntu/linux-oracle@6.17.0-1018.18?arch=source&distro=questingOther 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
An official patch is available and has been released by Ubuntu and other Linux distributors. Users should update their Linux kernel packages to the fixed versions listed in the vendor advisory and reboot their systems to apply the changes. Due to an ABI change, third-party kernel modules must be recompiled and reinstalled after updating. No additional mitigations are required beyond applying the official fix.
Description
A vulnerability in the Linux kernel's networking subsystem involving hardened usercopy was resolved. The flaw caused a kernel panic when CONFIG_HARDENED_USERCOPY was enabled due to missing usercopy whitelist definitions in skbuff_fclone_cache. This led to a BUG() during copying of socket error queue data to userspace. The issue affects multiple Linux kernel versions prior to specific patched releases and has been fixed in updated kernel packages. The vulnerability has a medium severity score and no known exploits in the wild. Users should apply the official patches and reboot to mitigate the issue.
References
- ubuntu.com/security/CVE-2026-22977 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-22977 (opens in a new tab)
- git.kernel.org/linus/2a71a1a8d0ed718b1c7a9ac61f07e5755c47ae20 (opens in a new tab)
- git.kernel.org/stable/c/005671c60fcf1dbdb8bddf12a62568fd5e4ec391 (opens in a new tab)
- git.kernel.org/stable/c/2a71a1a8d0ed718b1c7a9ac61f07e5755c47ae20 (opens in a new tab)
- git.kernel.org/stable/c/582a5e922a9652fcbb7d0165c95d5b20aa37575d (opens in a new tab)
- git.kernel.org/stable/c/88dd6be7ebb3153b662c2cebcb06e032a92857f5 (opens in a new tab)
- git.kernel.org/stable/c/8c6901aa29626e35045130bac09b75f791acca85 (opens in a new tab)
- git.kernel.org/stable/c/c655d2167bf014d4c61b4faeca59b60ff9b9f6b1 (opens in a new tab)
- git.kernel.org/stable/c/e00b169eaac5f7cdbf710c354c8fa76d02009115 (opens in a new tab)
- ubuntu.com/security/notices/USN-8096-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8096-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8096-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8096-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8116-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8096-5 (opens in a new tab)
- ubuntu.com/security/notices/USN-8141-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8163-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8163-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8243-1 (opens in a new tab)