CyberRota Analysis
AI-GeneratedThe vulnerability affects the Linux kernel's NFC (Near Field Communication) subsystem, specifically within the TLV (Type-Length-Value) parsing functions, which can lead to infinite loops or out-of-bounds (OOB) reads due to improper handling of offsets and buffer lengths. Exploitation of these flaws could allow an attacker to cause denial of service or potentially read sensitive data from memory. Organizations using affected Linux versions, particularly those implementing NFC functionalities, should prioritize patching this vulnerability to mitigate the risks associated with unauthorized access and system instability.
Original NVD Description
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.