CVE-2026-72057
net/sched: act_ct: preserve tc_skb_cb across defragmentation
- Published
- Updated
- Reserved
- Assigned by
- Linux
Description
In the Linux kernel, the following vulnerability has been resolved: net/sched: act_ct: preserve tc_skb_cb across defragmentation tcf_ct_handle_fragments() calls nf_ct_handle_fragments() without saving and restoring skb->cb. The defrag helper clears IPCB/IP6CB, which aliases the tc_skb_cb/qdisc_skb_cb control buffer. Fragmented traffic through act_ct therefore loses qdisc metadata such as pkt_segs and can trigger WARN_ON_ONCE() in qdisc_pkt_segs() when panic_on_warn is enabled. Save and restore the full tc_skb_cb around nf_ct_handle_fragments(), matching the pattern used by ovs_ct_handle_fragments().
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High8.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H |
| NVDNVD · Received | 3.1 | High8.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H |
- EPSS (exploitation in 30 days)
- 0.58% · top 52% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.2.
Weakness
Affected products
- affected 0d76daf2013ce1da20eab5e26bd81d983e1c18fb – < fb080b6f54835d5d4d11ce3122800e6f0f6689e6
- affected ec624fe740b416fb68d536b37fb8eef46f90b5c2 – < 67d6b00a54446c008f52cf70fc0c2ad0c712f85d
- affected ec624fe740b416fb68d536b37fb8eef46f90b5c2 – < 2400c4b05d58834b994500a9eec90a37db44187c
- affected ec624fe740b416fb68d536b37fb8eef46f90b5c2 – < 5c3ae5f6c7c6de73ea9b6a75154fe4ed343e1bac
- affected ec624fe740b416fb68d536b37fb8eef46f90b5c2 – < b3d835407846134b0d54637c0281b39bebef831d
- affected ec624fe740b416fb68d536b37fb8eef46f90b5c2 – < f7f45ceb855d9ba1cba594fb3f383255f7013fad
- affected ec624fe740b416fb68d536b37fb8eef46f90b5c2 – < 9092e15defbe6c7bc241c306093ca9d358a578e7
- affected 5.15.13 – < 5.15.217
- affected 5.16
- unaffected < 5.16
- unaffected 5.15.217 – ≤ 5.15.*
- unaffected 6.1.184 – ≤ 6.1.*
- unaffected 6.6.145 – ≤ 6.6.*
- unaffected 6.12.97 – ≤ 6.12.*
- unaffected 6.18.40 – ≤ 6.18.*
- unaffected 7.1.5 – ≤ 7.1.*
- unaffected 7.2 – ≤ *
References (7)
- https://git.kernel.org/stable/c/fb080b6f54835d5d4d11ce3122800e6f0f6689e6 (opens in a new tab)
- https://git.kernel.org/stable/c/67d6b00a54446c008f52cf70fc0c2ad0c712f85d (opens in a new tab)
- https://git.kernel.org/stable/c/2400c4b05d58834b994500a9eec90a37db44187c (opens in a new tab)
- https://git.kernel.org/stable/c/5c3ae5f6c7c6de73ea9b6a75154fe4ed343e1bac (opens in a new tab)
- https://git.kernel.org/stable/c/b3d835407846134b0d54637c0281b39bebef831d (opens in a new tab)
- https://git.kernel.org/stable/c/f7f45ceb855d9ba1cba594fb3f383255f7013fad (opens in a new tab)
- https://git.kernel.org/stable/c/9092e15defbe6c7bc241c306093ca9d358a578e7 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-72057)Record last updated .