CVE-2026-43011
Description
In the Linux kernel, the following vulnerability has been resolved: net/x25: Fix potential double free of skb When alloc_skb fails in x25_queue_rx_frame it calls kfree_skb(skb) at line 48 and returns 1 (error). This error propagates back through the call chain: x25_queue_rx_frame returns 1 | v x25_state3_machine receives the return value 1 and takes the else branch at line 278, setting queued=0 and returning 0 | v x25_process_rx_frame returns queued=0 | v x25_backlog_rcv at line 452 sees queued=0 and calls kfree_skb(skb) again This would free the same skb twice. Looking at x25_backlog_rcv: net/x25/x25_in.c:x25_backlog_rcv() { ... queued = x25_process_rx_frame(sk, skb); ... if (!queued) kfree_skb(skb); }
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2026-43011
Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2026-43011.html
Vendor advisory: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 — https://git.kernel.org/stable/c/fa1dbc93530b34fab0da9862426fe9c918c74dc0
Vendor advisory: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 — https://git.kernel.org/stable/c/f782dd382203b2a8c4552a628431b7de65a19a7b
Vendor advisory: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 — https://git.kernel.org/stable/c/d10a26aa4d072320530e6968ef945c8c575edf61
Vendor advisory: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 — https://git.kernel.org/stable/c/c87dd137c0dad07cc55f98181ff380b0c23d2878
Vendor advisory: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 — https://git.kernel.org/stable/c/5d0aa038a90b30c9bedde0c41c1fdcd98ecb16e9
Vendor advisory: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 — https://git.kernel.org/stable/c/524371398d8463ea7e101fce2cbf3915645d1730
Vendor advisory: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 — https://git.kernel.org/stable/c/3f5e3005984645bf5bd129c6b13149879580b1fb
Vendor advisory: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 — https://git.kernel.org/stable/c/143d4fa68ae9efb83b0c55b12cc7f0d03732a2b1
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| sles | affected | | |
| debian | bookworm | fixed | 6.1.170-1 |
| debian | bullseye | fixed | 6.1.170-1~deb11u1 |
| debian | forky | fixed | 6.19.12-1 |
| debian | sid | fixed | 6.19.12-1 |
| debian | trixie | fixed | 6.12.85-1 |
| linux-kernel | affected | 5.10.253 | |
| linux-kernel | 2.6.12 | affected | |
| linux-kernel | 7.0 | affected | |
References
- https://git.kernel.org/stable/c/143d4fa68ae9efb83b0c55b12cc7f0d03732a2b1
- https://git.kernel.org/stable/c/3f5e3005984645bf5bd129c6b13149879580b1fb
- https://git.kernel.org/stable/c/524371398d8463ea7e101fce2cbf3915645d1730
- https://git.kernel.org/stable/c/5d0aa038a90b30c9bedde0c41c1fdcd98ecb16e9
- https://git.kernel.org/stable/c/c87dd137c0dad07cc55f98181ff380b0c23d2878
- https://git.kernel.org/stable/c/d10a26aa4d072320530e6968ef945c8c575edf61
- https://git.kernel.org/stable/c/f782dd382203b2a8c4552a628431b7de65a19a7b
- https://git.kernel.org/stable/c/fa1dbc93530b34fab0da9862426fe9c918c74dc0
- https://www.suse.com/security/cve/CVE-2026-43011.html
- https://security-tracker.debian.org/tracker/CVE-2026-43011
CWEs
CWE-415
Verify integrity in audit chain (admin only). AS-IS.