{"id":"CVE-2026-80799","title":"nfc: llcp: fix OOB read and u8 offset wrap in TLV parsers","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfc: llcp: fix OOB read and u8 offset wrap in TLV parsers\n\nnfc_llcp_parse_gb_tlv() and nfc_llcp_parse_connection_tlv() contain\nthree related bugs in their TLV parsing l…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 0be9de2ea01e8d52646e7310a7eef5459cf07ea8 < 2c1456fe09ab1a5a9fe1d8339ca6d509589b56e1","Linux >= 3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < 7f6f3d087c67a4346189ef2c36481455bbc59a74","Linux >= 3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < 9c47d667963542c3cf8e3007b7f10c0904d08238","Linux >= 3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < a209334ed929941b20810c17c3a507445b0a7c85","Linux >= 3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < 382eaa770335acf4f16a5a55524500f2bb4207df","Linux >= 3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < 2d239590d1845a706304833d40dd6d4fec20ad88","Linux >= 3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < e84cdfdc4a6c88e8b751144458f2e04e24415a28","Linux >= 3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < 875285a165fd3b402de2ab3be0deb355d6f4caf5","Linux >= 3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < 78b20c8eeacd2e44a2d8a4cb5316d3c521d90911","Linux 1deacb5e031e289ca5636f2db4fcae6612c05d34","Linux 66a1be74230bbe098e651766c9a0cf4038db8442","Linux >= 5.10.188 < 5.10.267","Linux >= 4.19.291 < 4.20","Linux >= 5.4.251 < 5.5","Linux 5.15"],"published":"2026-09-04","updated":"2026-10-19","sourceUpdated":"2026-10-19T08:43:52.451Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-80799","references":[{"url":"https://git.kernel.org/stable/c/2c1456fe09ab1a5a9fe1d8339ca6d509589b56e1"},{"url":"https://git.kernel.org/stable/c/7f6f3d087c67a4346189ef2c36481455bbc59a74"},{"url":"https://git.kernel.org/stable/c/9c47d667963542c3cf8e3007b7f10c0904d08238"},{"url":"https://git.kernel.org/stable/c/a209334ed929941b20810c17c3a507445b0a7c85"},{"url":"https://git.kernel.org/stable/c/382eaa770335acf4f16a5a55524500f2bb4207df"},{"url":"https://git.kernel.org/stable/c/2d239590d1845a706304833d40dd6d4fec20ad88"},{"url":"https://git.kernel.org/stable/c/e84cdfdc4a6c88e8b751144458f2e04e24415a28"},{"url":"https://git.kernel.org/stable/c/875285a165fd3b402de2ab3be0deb355d6f4caf5"},{"url":"https://git.kernel.org/stable/c/78b20c8eeacd2e44a2d8a4cb5316d3c521d90911"}],"tags":["cve.org"],"epss":0.00234,"epssPercentile":0.13287,"ingestedAt":"2026-10-19T09:16:01.527Z","slug":"CVE-2026-80799","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnfc: llcp: fix OOB read and u8 offset wrap in TLV parsers\n\nnfc_llcp_parse_gb_tlv() and nfc_llcp_parse_connection_tlv() contain\nthree related bugs in their TLV parsing loops:\n\n1. 'offset' is declared u8 but tlv_array_len is u16. When TLV data\n   advances offset past 255 it silently wraps to zero, causing\n   infinite loops or double-processing of buffer data.\n\n2. Before reading tlv[0] (type) and tlv[1] (length) there is no\n   check that offset+2 <= tlv_array_len. A truncated TLV causes\n   an OOB read of one byte past the buffer end.\n\n3. After reading the length field, the value bytes are accessed\n   without checking offset+2+length <= tlv_array_len. A crafted\n   length=0xFF on a short buffer causes up to 255 bytes of OOB\n   read past the buffer end.\n\nBoth functions are reachable without authentication via\nnfc_llcp_set_remote_gb() which feeds remote LLCP general bytes\ndirectly into nfc_llcp_parse_gb_tlv() with no additional\nvalidation.\n\nFix all three issues by widening offset from u8 to u16 and adding\nbounds checks for both the TLV header and value field before each\naccess.\n\n## Affected\n\n- `Linux >= 0be9de2ea01e8d52646e7310a7eef5459cf07ea8 < 2c1456fe09ab1a5a9fe1d8339ca6d509589b56e1`\n- `Linux >= 3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < 7f6f3d087c67a4346189ef2c36481455bbc59a74`\n- `Linux >= 3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < 9c47d667963542c3cf8e3007b7f10c0904d08238`\n- `Linux >= 3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < a209334ed929941b20810c17c3a507445b0a7c85`\n- `Linux >= 3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < 382eaa770335acf4f16a5a55524500f2bb4207df`\n- `Linux >= 3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < 2d239590d1845a706304833d40dd6d4fec20ad88`\n- `Linux >= 3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < e84cdfdc4a6c88e8b751144458f2e04e24415a28`\n- `Linux >= 3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < 875285a165fd3b402de2ab3be0deb355d6f4caf5`\n- `Linux >= 3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < 78b20c8eeacd2e44a2d8a4cb5316d3c521d90911`\n- `Linux 1deacb5e031e289ca5636f2db4fcae6612c05d34`\n- `Linux 66a1be74230bbe098e651766c9a0cf4038db8442`\n- `Linux >= 5.10.188 < 5.10.267`\n- `Linux >= 4.19.291 < 4.20`\n- `Linux >= 5.4.251 < 5.5`\n- `Linux 5.15`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}