CVE-2026-43238
Description
In the Linux kernel, the following vulnerability has been resolved: net/sched: act_skbedit: fix divide-by-zero in tcf_skbedit_hash() Commit 38a6f0865796 ("net: sched: support hash selecting tx queue") added SKBEDIT_F_TXQ_SKBHASH support. The inclusive range size is computed as: mapping_mod = queue_mapping_max - queue_mapping + 1; The range size can be 65536 when the requested range covers all possible u16 queue IDs (e.g. queue_mapping=0 and queue_mapping_max=U16_MAX). That value cannot be represented in a u16 and previously wrapped to 0, so tcf_skbedit_hash() could trigger a divide-by-zero: queue_mapping += skb_get_hash(skb) % params->mapping_mod; Compute mapping_mod in a wider type and reject ranges larger than U16_MAX to prevent params->mapping_mod from becoming 0 and avoid the crash.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| sles | affected | | |
| debian | bookworm | fixed | 6.1.170-1 |
| debian | bullseye | fixed | 0 |
| debian | forky | fixed | 6.19.6-1 |
| debian | sid | fixed | 6.19.6-1 |
| debian | trixie | fixed | 6.12.85-1 |
| linux-kernel | affected | 6.1.165 |
References
- https://git.kernel.org/stable/c/015cebdfcb97b5347fb7f598ea712a281cb35840
- https://git.kernel.org/stable/c/3c2b95b26860bd6f8e2310d31ea1200d3f8f173e
- https://git.kernel.org/stable/c/4ece5eb4836f8ff03b9004dc2430a7169f282851
- https://git.kernel.org/stable/c/59809fda4da7730cfe84a948033f47eb45db073d
- https://git.kernel.org/stable/c/9c735a7d98c982a786b0db71eb6566ee00aaa04f
- https://git.kernel.org/stable/c/be054cc66f739a9ba615dba9012a07fab8e7dd6f
- https://www.suse.com/security/cve/CVE-2026-43238.html
- https://security-tracker.debian.org/tracker/CVE-2026-43238
CWEs
CWE-369
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.