CVE-2026-31622
Description
In the Linux kernel, the following vulnerability has been resolved: NFC: digital: Bounds check NFC-A cascade depth in SDD response handler The NFC-A anti-collision cascade in digital_in_recv_sdd_res() appends 3 or 4 bytes to target->nfcid1 on each round, but the number of cascade rounds is controlled entirely by the peer device. The peer sets the cascade tag in the SDD_RES (deciding 3 vs 4 bytes) and the cascade-incomplete bit in the SEL_RES (deciding whether another round follows). ISO 14443-3 limits NFC-A to three cascade levels and target->nfcid1 is sized accordingly (NFC_NFCID1_MAXSIZE = 10), but nothing in the driver actually enforces this. This means a malicious peer can keep the cascade running, writing past the heap-allocated nfc_target with each round. Fix this by rejecting the response when the accumulated UID would exceed the buffer. Commit e329e71013c9 ("NFC: nci: Bounds check struct nfc_target arrays") fixed similar missing checks against the same field on the NCI path.
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
Linux kernel Affected 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Affected | 6.6.136 |
SUSE Affected 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Affected | — |
Debian Mixed 5 releases
| Version | Status | Fixed in |
|---|---|---|
| trixie | Fixed | 6.12.85-1 |
| sid | Fixed | 6.19.14-1 |
| forky | Fixed | 6.19.14-1 |
| bullseye | Affected | — |
| bookworm | Affected | — |
References
- https://git.kernel.org/stable/c/1bec5698b55aa2be5c3b983dba657c01d0fd3dbc
- https://git.kernel.org/stable/c/2819f34e08bdffb6f06a51c67948ec5737fb166a
- https://git.kernel.org/stable/c/46ce8be2ced389bccd84bcc04a12cf2f4d0c22d1
- https://git.kernel.org/stable/c/5a59bf70c38ee1eb4be03bab830bbc3a6f0bd1f1
- https://git.kernel.org/stable/c/8d9d9bf3565271ca7ab9c716a94e87296177e7ba
- https://git.kernel.org/stable/c/cc024a3de265ef6c58957f4990eccb9f806208cb
- https://www.suse.com/security/cve/CVE-2026-31622.html
- https://security-tracker.debian.org/tracker/CVE-2026-31622
- https://git.kernel.org/stable/c/20663102c14566e900e1d2f679e30b7f1694f387
- https://git.kernel.org/stable/c/9ba6bb09e00b922d902f684f575779e5433fe6e3
- https://git.kernel.org/stable/c/f83b399aa05a0712e3b1569a30d3d90b3533d2ef
CWEs
CWE-120
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.