CVE-2026-80800nfc: llcp: bound the connect_sn TLV walk to the skb
- —Not scoredno CVSS score yet
- 0.23%Exploitation in 30 daysEPSS · top 86% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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).
Timeline
ID reserved
By Linux
- 9 days later
· 9 days later
Published
- 45 days later
· 45 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
No CVSS score yet: neither the CNA, CISA nor NVD has scored this CVE. NVD status: Received.
- EPSS (exploitation in 30 days)
- 0.23% · top 86% of all CVEs (13 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Not scored.
Affected products
- affected d646960f7986fefb460a2b062d5ccc8ccfeacc3a – < b2ebdfe3d5b76e91f267a61cbc3f9a0e3f77071e
- affected d646960f7986fefb460a2b062d5ccc8ccfeacc3a – < e18d044bab6d3d0280639098c3fe6621692cbfe2
- affected d646960f7986fefb460a2b062d5ccc8ccfeacc3a – < 65a0ec7783b06068dda6745dd689bf4a91ee64aa
- affected d646960f7986fefb460a2b062d5ccc8ccfeacc3a – < 1964addc8dd535a05d5d3b55b4d1ac19ae31aa65
- affected d646960f7986fefb460a2b062d5ccc8ccfeacc3a – < 389986fd79e4d43f971a03b512645a1bb63c982f
- affected d646960f7986fefb460a2b062d5ccc8ccfeacc3a – < e87527b506c40db9af528714b7b1240918eb80fc
- affected d646960f7986fefb460a2b062d5ccc8ccfeacc3a – < 22e5177ba1196a0b272a6a46c2575eb940a939c4
- affected d646960f7986fefb460a2b062d5ccc8ccfeacc3a – < 0cfbdb0e13ab5b0765d77f96af67eb879cbc9736
- affected d646960f7986fefb460a2b062d5ccc8ccfeacc3a – < 55c68ac93e7dacc0f5f608b9c39dd4ff48cf28e8
- affected 3.3
- unaffected < 3.3
- unaffected 5.10.267 – ≤ 5.10.*
- unaffected 5.15.218 – ≤ 5.15.*
- unaffected 6.1.185 – ≤ 6.1.*
- unaffected 6.6.154 – ≤ 6.6.*
- unaffected 6.12.106 – ≤ 6.12.*
- unaffected 6.18.47 – ≤ 6.18.*
- unaffected 7.1.11 – ≤ 7.1.*
- unaffected 7.2.1 – ≤ 7.2.*
- unaffected 7.3 – ≤ *
References
References9
- https://git.kernel.org/stable/c/b2ebdfe3d5b76e91f267a61cbc3f9a0e3f77071e (opens in a new tab)
- https://git.kernel.org/stable/c/e18d044bab6d3d0280639098c3fe6621692cbfe2 (opens in a new tab)
- https://git.kernel.org/stable/c/65a0ec7783b06068dda6745dd689bf4a91ee64aa (opens in a new tab)
- https://git.kernel.org/stable/c/1964addc8dd535a05d5d3b55b4d1ac19ae31aa65 (opens in a new tab)
- https://git.kernel.org/stable/c/389986fd79e4d43f971a03b512645a1bb63c982f (opens in a new tab)
- https://git.kernel.org/stable/c/e87527b506c40db9af528714b7b1240918eb80fc (opens in a new tab)
- https://git.kernel.org/stable/c/22e5177ba1196a0b272a6a46c2575eb940a939c4 (opens in a new tab)
- https://git.kernel.org/stable/c/0cfbdb0e13ab5b0765d77f96af67eb879cbc9736 (opens in a new tab)
- https://git.kernel.org/stable/c/55c68ac93e7dacc0f5f608b9c39dd4ff48cf28e8 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-71235 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
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[](https://cveledger.app/cve/CVE-2026-80800)Record last updated .