{"id":"CVE-2026-80823","summary":"nfc: st21nfca: validate ATR_REQ length against the received frame","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfc: st21nfca: validate ATR_REQ length against the received frame\n\nst21nfca_tm_recv_atr_req() checks that the received ATR_REQ frame is at\nleast ST21NFCA_ATR_REQ_MIN_SIZE and that the self-declared atr_req-\u003elength\nis at least sizeof(struct st21nfca_atr_req), but never checks that\natr_req-\u003elength does not exceed the actual received length (skb-\u003elen).\n\nst21nfca_tm_send_atr_res() then trusts the declared length:\n\n\tgb_len = atr_req-\u003elength - sizeof(struct st21nfca_atr_req);\n\t...\n\tmemcpy(atr_res-\u003egbi, atr_req-\u003egbi, gb_len);\n\nso an RF peer that sends a short frame but sets atr_req-\u003elength larger\nthan the frame makes gb_len exceed the general bytes actually present,\nand the memcpy reads out of bounds past the received skb. Those bytes are\nplaced in the ATR_RES and sent back to the peer (kernel-memory disclosure\nto a proximity attacker); a larger declared length is an out-of-bounds\nread (DoS).\n\nReject frames whose declared length exceeds the received length. The\nadjacent nfc_tm_activated() path in the same function already derives its\ngeneral-bytes length from skb-\u003elen rather than the declared field.\n\nFound by 0sec (https://0sec.ai) using automated source analysis; the\nmissing bound is evident from source. Compile-tested.","modified":"2026-09-06T03:46:51.894931761Z","published":"2026-09-04T15:27:46.153Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80823.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/0f344944c506b4f02d2b098489f7268b438c369e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2c1ad291f4cdc357f9527b688c6fda9c6ffa7890"},{"type":"WEB","url":"https://git.kernel.org/stable/c/304f5b414f4051d324b8c4a3ab0e79f7dc7e150e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5cdcca5d62a66eda6b774110a44cba67bc1a8d1d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/785df00bb3ae3206674a43284eb06dac575b5c64"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9635507fe82949e429b3cd938876a9917125b151"},{"type":"WEB","url":"https://git.kernel.org/stable/c/bfcca5f42c9aa4eadef1e5fe7bb23783d7fcc96d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/dd26d30f40c43ad9cfe2f25c6ea0ead1dd51d5aa"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f33cecf69095c43be88567fef92b180b858f7369"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80823.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-80823"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"1892bf844ea0261736bd5e75546fc996e9daeedf"},{"fixed":"785df00bb3ae3206674a43284eb06dac575b5c64"},{"fixed":"2c1ad291f4cdc357f9527b688c6fda9c6ffa7890"},{"fixed":"dd26d30f40c43ad9cfe2f25c6ea0ead1dd51d5aa"},{"fixed":"9635507fe82949e429b3cd938876a9917125b151"},{"fixed":"0f344944c506b4f02d2b098489f7268b438c369e"},{"fixed":"bfcca5f42c9aa4eadef1e5fe7bb23783d7fcc96d"},{"fixed":"304f5b414f4051d324b8c4a3ab0e79f7dc7e150e"},{"fixed":"f33cecf69095c43be88567fef92b180b858f7369"},{"fixed":"5cdcca5d62a66eda6b774110a44cba67bc1a8d1d"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80823.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.17.0"},{"fixed":"5.10.267"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.218"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.185"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.154"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.106"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.47"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.11"}]},{"type":"ECOSYSTEM","events":[{"introduced":"7.2.0"},{"fixed":"7.2.1"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80823.json"}}],"schema_version":"1.9.0"}