CVE-2026-80799

Summary

In the Linux kernel, the following vulnerability has been resolved:

nfc: llcp: fix OOB read and u8 offset wrap in TLV parsers

nfc_llcp_parse_gb_tlv() and nfc_llcp_parse_connection_tlv() contain three related bugs in their TLV parsing loops:

  1. 'offset' is declared u8 but tlv_array_len is u16. When TLV data advances offset past 255 it silently wraps to zero, causing infinite loops or double-processing of buffer data.

  2. Before reading tlv[0] (type) and tlv[1] (length) there is no check that offset+2 <= tlv_array_len. A truncated TLV causes an OOB read of one byte past the buffer end.

  3. After reading the length field, the value bytes are accessed without checking offset+2+length <= tlv_array_len. A crafted length=0xFF on a short buffer causes up to 255 bytes of OOB read past the buffer end.

Both functions are reachable without authentication via nfc_llcp_set_remote_gb() which feeds remote LLCP general bytes directly into nfc_llcp_parse_gb_tlv() with no additional validation.

Fix all three issues by widening offset from u8 to u16 and adding bounds checks for both the TLV header and value field before each access.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux0be9de2ea01e8d52646e7310a7eef5459cf07ea8 < 2c1456fe09ab1a5a9fe1d8339ca6d509589b56e1affected
LinuxLinux3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < 7f6f3d087c67a4346189ef2c36481455bbc59a74affected
LinuxLinux3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < 9c47d667963542c3cf8e3007b7f10c0904d08238affected
LinuxLinux3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < a209334ed929941b20810c17c3a507445b0a7c85affected
LinuxLinux3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < 382eaa770335acf4f16a5a55524500f2bb4207dfaffected
LinuxLinux3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < 2d239590d1845a706304833d40dd6d4fec20ad88affected
LinuxLinux3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < e84cdfdc4a6c88e8b751144458f2e04e24415a28affected
LinuxLinux3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < 875285a165fd3b402de2ab3be0deb355d6f4caf5affected
LinuxLinux3df40eb3a2ea58bf404a38f15a7a2768e4762cb0 < 78b20c8eeacd2e44a2d8a4cb5316d3c521d90911affected
LinuxLinux1deacb5e031e289ca5636f2db4fcae6612c05d34affected
LinuxLinux66a1be74230bbe098e651766c9a0cf4038db8442affected
LinuxLinux5.10.188 < 5.10.267affected
LinuxLinux4.19.291 < 4.20affected
LinuxLinux5.4.251 < 5.5affected
LinuxLinux5.15affected
LinuxLinux0 < 5.15unaffected
LinuxLinux5.10.267 <= 5.10.*unaffected
LinuxLinux5.15.218 <= 5.15.*unaffected
LinuxLinux6.1.185 <= 6.1.*unaffected
LinuxLinux6.6.154 <= 6.6.*unaffected
LinuxLinux6.12.106 <= 6.12.*unaffected
LinuxLinux6.18.47 <= 6.18.*unaffected
LinuxLinux7.1.11 <= 7.1.*unaffected
LinuxLinux7.2.1 <= 7.2.*unaffected
LinuxLinux7.3-rc1 <= *unaffected

Weaknesses

References