CVE-2026-31472
Description
In the Linux kernel, the following vulnerability has been resolved: xfrm: iptfs: validate inner IPv4 header length in IPTFS payload Add validation of the inner IPv4 packet tot_len and ihl fields parsed from decrypted IPTFS payloads in __input_process_payload(). A crafted ESP packet containing an inner IPv4 header with tot_len=0 causes an infinite loop: iplen=0 leads to capturelen=min(0, remaining)=0, so the data offset never advances and the while(data < tail) loop never terminates, spinning forever in softirq context. Reject inner IPv4 packets where tot_len < ihl*4 or ihl*4 < sizeof(struct iphdr), which catches both the tot_len=0 case and malformed ihl values. The normal IP stack performs this validation in ip_rcv_core(), but IPTFS extracts and processes inner packets before they reach that layer.
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 | 0 |
| debian | bullseye | fixed | 0 |
| debian | forky | fixed | 6.19.11-1 |
| debian | sid | fixed | 6.19.11-1 |
| debian | trixie | fixed | 0 |
| linux-kernel | affected | 6.18.21 | |
| linux-kernel | 6.14 | affected | |
| linux-kernel | 7.0 | affected | |
References
- https://git.kernel.org/stable/c/0d10393d5eac33cbd92f7a41fddca12c41d3cb7e
- https://git.kernel.org/stable/c/3db7d4f777a00164582061ccaa99569cd85011a3
- https://git.kernel.org/stable/c/de6d8e8ce5187f7402c9859b443355e7120c5f09
- https://www.suse.com/security/cve/CVE-2026-31472.html
- https://security-tracker.debian.org/tracker/CVE-2026-31472
CWEs
CWE-835
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.