Unknown

CVE-2026-80800 — nfc: llcp: bound the connect_sn TLV walk to the skb

In the Linux kernel, the following vulnerability has been resolved: nfc: llcp: bound the connect_sn TLV walk to the skb Commit 27256cdb290e ("nfc: llcp: bound SNL TLV parsing to the skb and add length checks") fixed the unbounded TLV walk in nfc_llcp_recv_snl(), and commit d8bd2dedbde5 ("nfc: llcp: fix OOB read and u8 offset wrap in TLV parsers") subsequently bounded nfc_llcp_parse_gb_tlv() and nfc_llcp_parse_connection_tlv(). One sibling parser sharing the same pattern remains unbounded: nfc_llcp_connect_sn(). nfc_llcp_connect_sn() walks a TLV list, reading a two-byte header (type, length) followed by length bytes of value, without checking that the two header bytes or the declared length stay within the buffer. It returns a pointer to a service name of up to 255 bytes that may point past the end of the skb; it is subsequently consumed by memcmp() in nfc_llcp_sock_from_sn(). In addition tlv_array_len was computed as "skb->len - LLCP_HEADER_SIZE" in size_t, so a CONNECT/CC frame shorter than the LLCP header underflows to a huge length and the walk runs far past the buffer. nfc_llcp_connect_sn() is reachable from nfc_llcp_recv_connect() and nfc_llcp_recv_cc(), i.e. from received CONNECT and CC PDUs. A nearby NFC device can reach this without authentication; LLCP link activation happens automatically after NFC-DEP, and the nfc_llcp_rx_skb() dispatcher applies no minimum-length guard. Walk the TLV list by pointer, bounded by skb_tail_pointer(skb), and validate each declared length before use, matching the approach already used for nfc_llcp_recv_snl(). Starting the walk at &skb->data[LLCP_HEADER_SIZE] against the tail pointer also removes the size_t underflow for short frames. Found by 0sec automated security-research tooling (https://0sec.ai).

Published Sep 4, 2026 · Updated Oct 15, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: Linux

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.2% (30-day exploitation probability)+2

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.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.23%

ahead of 14% of scored CVEs · Oct 26, 2026

Affects

Linux

CVSS base

—

Score not published yet.

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

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).
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Linux	Linux	≥ d646960f7986fefb460a2b062d5ccc8ccfeacc3a and < b2ebdfe3d5b76e91f267a61cbc3f9a0e3f77071e≥ d646960f7986fefb460a2b062d5ccc8ccfeacc3a and < e18d044bab6d3d0280639098c3fe6621692cbfe2≥ d646960f7986fefb460a2b062d5ccc8ccfeacc3a and < 65a0ec7783b06068dda6745dd689bf4a91ee64aa≥ d646960f7986fefb460a2b062d5ccc8ccfeacc3a and < 1964addc8dd535a05d5d3b55b4d1ac19ae31aa65≥ d646960f7986fefb460a2b062d5ccc8ccfeacc3a and < 389986fd79e4d43f971a03b512645a1bb63c982f≥ d646960f7986fefb460a2b062d5ccc8ccfeacc3a and < e87527b506c40db9af528714b7b1240918eb80fc≥ d646960f7986fefb460a2b062d5ccc8ccfeacc3a and < 22e5177ba1196a0b272a6a46c2575eb940a939c4≥ d646960f7986fefb460a2b062d5ccc8ccfeacc3a and < 0cfbdb0e13ab5b0765d77f96af67eb879cbc9736 and 2 more ≥ d646960f7986fefb460a2b062d5ccc8ccfeacc3a and < 55c68ac93e7dacc0f5f608b9c39dd4ff48cf28e8version 3.3	Vulnerable	CVE Program (cve.org) e CISA ADP

EPSS over time FIRST

Oct 15, 2026 → Oct 26, 2026 · 11 reading(s) · max 0.29%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Not enough vector or weakness data: use the affected application’s logs as a starting point.

application logs

Timeline

What happened to this CVE, newest first.

2026
Record published
Oct 15, 2026
Affected products added · linux/linux
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
Source status changed · → Received
Oct 15, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 15, 2026 · NIST National Vulnerability Database
CVE published
Sep 4, 2026 · Linux

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

9 on the record

git.kernel.org/stable/c/389986fd79e4d43f971a03b512645a1bb63c982f
NIST National Vulnerability Database
git.kernel.org/stable/c/0cfbdb0e13ab5b0765d77f96af67eb879cbc9736
NIST National Vulnerability Database
git.kernel.org/stable/c/22e5177ba1196a0b272a6a46c2575eb940a939c4
NIST National Vulnerability Database
git.kernel.org/stable/c/55c68ac93e7dacc0f5f608b9c39dd4ff48cf28e8
NIST National Vulnerability Database
git.kernel.org/stable/c/1964addc8dd535a05d5d3b55b4d1ac19ae31aa65
NIST National Vulnerability Database
git.kernel.org/stable/c/b2ebdfe3d5b76e91f267a61cbc3f9a0e3f77071e
NIST National Vulnerability Database
git.kernel.org/stable/c/e18d044bab6d3d0280639098c3fe6621692cbfe2
NIST National Vulnerability Database
git.kernel.org/stable/c/e87527b506c40db9af528714b7b1240918eb80fc
NIST National Vulnerability Database
git.kernel.org/stable/c/65a0ec7783b06068dda6745dd689bf4a91ee64aa
NIST National Vulnerability Database

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

Unknown CVE-2026-99092 riscv: patch: fix handling of bpf-jit execmem addresses 14h
Unknown CVE-2026-99093 mm: don't schedule deferred kernel page table freeing while booting 14h
Unknown CVE-2026-99095 drm/vc4: drain the hangcheck timer and works on V3D unbind 14h
Unknown CVE-2026-99096 io_uring/register: don't exempt disabled rings from task restrictions 14h
Unknown CVE-2026-99097 tee: shm: reject zero-sized allocations in tee_dyn_shm_alloc_helper() 14h
Unknown CVE-2026-99098 dm-integrity: fix buffer overflow in inline mode with large tag size 14h

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 CVSS score published by NVD, the CNA, CISA or GitHub so far.
No fixed version, patch or mitigation documented.
No CISA SSVC assessment.
No CWE classification.
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-2026-80800 is "nfc: llcp: bound the connect_sn TLV walk to the skb", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.23% 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.

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