CVE-2026-23140: Linux kernel · bpf, test_run: Subtract size of xdp_frame from allowed metadata size
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.5 Medium · fixed in 6.8.0-1057.60~22.04.1 : update Linux kernel when convenient.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 3% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 6.8.0-1057.60~22.04.1, 6.8.0-1059.65~22.04.1, 6.8.0-1058.65~22.04.1 +37
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 14 Feb 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?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-oraclepkg:deb/ubuntu/linux-oracle?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
A patch is available and should be applied to affected Linux kernel versions. The issue has been fixed by adding proper validation of metadata size in the kernel code. Users should update to the fixed kernel versions as provided by their Linux distribution vendors. No additional mitigations are indicated by the vendor advisory.
Description
A vulnerability in the Linux kernel's BPF test_run functionality allows userspace to specify an excessively large metadata size that can exceed the XDP frame headroom. This can cause the xdp_update_frame_from_buff() function to fail and lead to packet transmission using an uninitialized frame structure, resulting in potential system instability or denial of service. The issue has been fixed by adding an additional check on the metadata size and reordering validation logic for clarity.
References
- ubuntu.com/security/CVE-2026-23140 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-23140 (opens in a new tab)
- git.kernel.org/linus/e558cca217790286e799a8baacd1610bda31b261 (opens in a new tab)
- git.kernel.org/stable/c/31e37f44b60679d90b9f999c91371b15291be8e0 (opens in a new tab)
- git.kernel.org/stable/c/6447e697cfa8a43a8e491cb81bcc390d0f28f8ba (opens in a new tab)
- git.kernel.org/stable/c/7c81ad5e580bd8441f8a521a8d34824ce6582ae5 (opens in a new tab)
- git.kernel.org/stable/c/e558cca217790286e799a8baacd1610bda31b261 (opens in a new tab)
- git.kernel.org/stable/c/e7440935063949d6f2c10f7328d960d0ff4bce90 (opens in a new tab)
- ubuntu.com/security/notices/USN-8278-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8289-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8296-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8296-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8289-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8278-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8393-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8440-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8499-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8570-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8594-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8604-1 (opens in a new tab)