CVE-2025-68363: Linux kernel · bpf: Check skb->transport_header is set in bpf_skb_check_mtu
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 1.8 Low · fixed in 6.8.0-1052.55~22.04.1 : update Linux kernel when convenient.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 11% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 6.8.0-1052.55~22.04.1, 6.8.0-1059.65~22.04.1, 6.8.0-1058.65~22.04.1 +43
CVSS:4.0/AV:L/AC:L/AT:P/PR:H/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 24 Dec 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.
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
An official patch is available and should be applied to affected linux-hwe-edge kernel versions. The vendor advisory confirms the issue is fixed in linux-hwe-6.17 kernel releases. Systems running affected versions should upgrade to the patched kernel versions to resolve this vulnerability. No additional mitigation steps are indicated by the vendor advisory.
Description
A vulnerability in the Linux kernel's BPF subsystem was addressed involving the bpf_skb_check_mtu helper. The issue stems from the helper using skb->transport_header without confirming it is set, which can cause warnings and potentially affect BPF program behavior. The fix involves adding a check to ensure skb_transport_header_was_set() before using skb->transport_header, preventing improper usage. This vulnerability affects certain versions of the linux-hwe-edge kernel prior to 6.8.0-1051.51~22.04.1 and related versions. The issue is medium severity and no known exploits are reported in the wild. A patch is available from the vendor.
References
- ubuntu.com/security/CVE-2025-68363 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-68363 (opens in a new tab)
- git.kernel.org/stable/c/1c30e4afc5507f0069cc09bd561e510e4d97fbf7 (opens in a new tab)
- git.kernel.org/stable/c/30ce906557a21adef4cba5901c8e995dc18263a9 (opens in a new tab)
- git.kernel.org/stable/c/942268e2726ac7f16e3ec49dbfbbbe7cf5af9da5 (opens in a new tab)
- git.kernel.org/stable/c/d946f3c98328171fa50ddb908593cf833587f725 (opens in a new tab)
- ubuntu.com/security/notices/USN-8094-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8094-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8094-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8094-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8094-5 (opens in a new tab)
- ubuntu.com/security/notices/USN-8152-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8179-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8184-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8179-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8185-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8179-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8203-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8204-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8185-2 (opens in a new tab)