CVE-2026-31622 — NFC: digital: Bounds check NFC-A cascade depth in SDD response handler
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.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.4% (30-day exploitation probability)+6
- Technical severity (high)+6
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Linux Linux, Linux Linux Kernel).
- Apply the fixed version or the patch documented under Remediation.
- Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux |
≥ 2c66daecc4092e6049673c281b2e6f0d5e59a94c and < 9ba6bb09e00b922d902f684f575779e5433fe6e3≥ 2c66daecc4092e6049673c281b2e6f0d5e59a94c and < f83b399aa05a0712e3b1569a30d3d90b3533d2ef≥ 2c66daecc4092e6049673c281b2e6f0d5e59a94c and < 20663102c14566e900e1d2f679e30b7f1694f387≥ 2c66daecc4092e6049673c281b2e6f0d5e59a94c and < 2819f34e08bdffb6f06a51c67948ec5737fb166a≥ 2c66daecc4092e6049673c281b2e6f0d5e59a94c and < 1bec5698b55aa2be5c3b983dba657c01d0fd3dbc≥ 2c66daecc4092e6049673c281b2e6f0d5e59a94c and < 5a59bf70c38ee1eb4be03bab830bbc3a6f0bd1f1≥ 2c66daecc4092e6049673c281b2e6f0d5e59a94c and < 8d9d9bf3565271ca7ab9c716a94e87296177e7ba≥ 2c66daecc4092e6049673c281b2e6f0d5e59a94c and < cc024a3de265ef6c58957f4990eccb9f806208cb and 2 more≥ 2c66daecc4092e6049673c281b2e6f0d5e59a94c and < 46ce8be2ced389bccd84bcc04a12cf2f4d0c22d1version 3.13 |
Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel | ≥ 3.13 and < 6.6.136≥ 6.7 and < 6.12.83≥ 6.13 and < 6.18.24≥ 6.19 and < 6.19.14≥ 7.0 and < 7.0.1 | Vulnerable | NIST National Vulnerability Database |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 8.8 | CVSS 3.1 | High | 2.8 | 5.9 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database |
| 8.8 | CVSS 3.1 | High | — | — | GitHub, Inc. via GitHub Security Advisories |
| 8.8 | CVSS 3.1 | High | — | — | Linux via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H (score shown at the top: 416baaa9-dc9f-4396-8d5f-8c081fb06d67) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.44%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · linux/linux
- Record published
- Fix documented
- CVSS changed · 8.8
- Source status changed · → Modified
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 2× References added · Oct 14, 2026 – Oct 14, 2026
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
12 on the record
- git.kernel.org/stable/c/1bec5698b55aa2be5c3b983dba657c01d0fd3dbc
- git.kernel.org/stable/c/5a59bf70c38ee1eb4be03bab830bbc3a6f0bd1f1
- git.kernel.org/stable/c/8d9d9bf3565271ca7ab9c716a94e87296177e7ba
- git.kernel.org/stable/c/46ce8be2ced389bccd84bcc04a12cf2f4d0c22d1
- git.kernel.org/stable/c/cc024a3de265ef6c58957f4990eccb9f806208cb
- git.kernel.org/stable/c/2819f34e08bdffb6f06a51c67948ec5737fb166a
- nvd.nist.gov/vuln/detail/CVE-2026-31622
- git.kernel.org/stable/c/f83b399aa05a0712e3b1569a30d3d90b3533d2ef
- git.kernel.org/stable/c/20663102c14566e900e1d2f679e30b7f1694f387
- git.kernel.org/stable/c/9ba6bb09e00b922d902f684f575779e5433fe6e3
- github.com/advisories/GHSA-3r85-565g-4jhq
- cert-portal.siemens.com/productcert/html/ssa-784472.html
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 13h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 13h
- Unknown CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 1d
- Unknown CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 1d
- Unknown CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 1d
- Unknown CVE-2026-98427 net/sched: codel: bound the dropping loop per dequeue call 1d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No CISA SSVC assessment.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-31622 is "NFC: digital: Bounds check NFC-A cascade depth in SDD response handler", rated High. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 8.8 describes technical severity. EPSS 0.44% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
Comments
Moderated technical discussion. Read the community guidelines.
No comments yet.
Sign in or create an account to comment and suggest corrections.