CVE-2026-80800

CVE CVE-2026-80800EUVD EUVD-2026-71235Veröffentlicht 2026-09-04T15:13:14.000Z

Was das Advisory beschreibt

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).

Quelle: EUVD (ENISA), im Wortlaut der Meldung.

Produkte, die das Advisory nennt

Diese Angaben stammen aus der Meldung selbst, nicht aus einer Prüfung durch uns.

• Linux — Linux d646960f7986fefb460a2b062d5ccc8ccfeacc3a <e18d044bab6d3d0280639098c3fe6621692cbfe2; patch: 6.12.106; patch: 7.3-rc1; patch: 5.15.218; patch: 5.10.267; d646960f7986fefb460a2b062d5ccc8ccfeacc3a <22e5177ba1196a0b272a6a46c2575eb940a939c4; d646960f7986fefb460a2b062d5ccc8ccfeacc3a <0cfbdb0e13ab5b0765d77f96af67eb879cbc9736; patch: 6.1.185; d646960f7986fefb460a2b062d5ccc8ccfeacc3a <389986fd79e4d43f971a03b512645a1bb63c982f; patch: 0; d646960f7986fefb460a2b062d5ccc8ccfeacc3a <1964addc8dd535a05d5d3b55b4d1ac19ae31aa65; d646960f7986fefb460a2b062d5ccc8ccfeacc3a <e87527b506c40db9af528714b7b1240918eb80fc; d646960f7986fefb460a2b062d5ccc8ccfeacc3a <b2ebdfe3d5b76e91f267a61cbc3f9a0e3f77071e; d646960f7986fefb460a2b062d5ccc8ccfeacc3a <55c68ac93e7dacc0f5f608b9c39dd4ff48cf28e8; d646960f7986fefb460a2b062d5ccc8ccfeacc3a <65a0ec7783b06068dda6745dd689bf4a91ee64aa; patch: 6.6.154; patch: 6.18.47; patch: 7.2.1; patch: 7.1.11; 3.3

Die genannten Versionen sind die Angabe der Meldung. Patchlage vergleicht keine Versionsnummern und leitet aus ihnen keine Aussage ab — welche Version installiert ist, muss ein Mensch nachsehen.

Im Produktkatalog geführt

Für diese Produkte kann ein Bestand in Patchlage erfasst werden. Ein Advisory dazu erscheint am Morgen danach im Lagebericht.

• Linux — Linux

Patchlage meldet Treffer und Verdachtsfälle. Zu allem anderen sagt dieses System nichts — weder diese Seite noch der Lagebericht behauptet je, dass ein Bestand sicher ist.