{"id":"CVE-2026-98600","title":"Bluetooth: RFCOMM: Reject short EA=0 frames in rfcomm_recv_frame()","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: RFCOMM: Reject short EA=0 frames in rfcomm_recv_frame()\n\nWhile rfcomm_recv_frame() verifies that skb->len is at least\nsizeof(*hdr) + 1 (4 bytes: 3-byte heade…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= fb40eda15122f6b780228639c1ead6820340ff54 < 76876fd26569302d26d91cbe8b75fa8e66cf8969","Linux >= 3829af5fab5a22405bf1e7d69068c2ec0fce46ca < 97711b964877242933484989224a3c4c5d88a5ee","Linux >= b161eacd7fa4a2d765724b5504ac6cc388e48f80 < 7a1781a2f3a9667b3065d402d1f11986a2363e08","Linux >= 30d1d9f3495463f7c026e4c553127f79b486fcd6 < c25587fa26761e623198b4f47151fe79d09ccde6","Linux >= 67dc3b40fae71b6b11c71e7ff69bac0758818c05 < 71ccacde407b7d8f0ef48974a0d2524602fd5c44","Linux >= bbc310caa2b6bf5fe42896ba27da0fbc12e4ac51 < be00deee60044ffa820f9436415caeb665b2cda0","Linux >= b230e5bf501c5edaf2eb0991cb862ac142031d4b < 9240fc1f2cde5331c61608da21b00394602ca762","Linux >= b230e5bf501c5edaf2eb0991cb862ac142031d4b < 6d91041bb38b97e2feb625123cc0529d7b83a0e1","Linux >= 6.12.111 < 6.12.112","Linux >= 6.18.53 < 6.18.55","Linux 7.2"],"published":"2026-10-18","updated":"2026-10-18","sourceUpdated":"2026-10-18T15:19:12.864Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98600","references":[{"url":"https://git.kernel.org/stable/c/76876fd26569302d26d91cbe8b75fa8e66cf8969"},{"url":"https://git.kernel.org/stable/c/97711b964877242933484989224a3c4c5d88a5ee"},{"url":"https://git.kernel.org/stable/c/7a1781a2f3a9667b3065d402d1f11986a2363e08"},{"url":"https://git.kernel.org/stable/c/c25587fa26761e623198b4f47151fe79d09ccde6"},{"url":"https://git.kernel.org/stable/c/71ccacde407b7d8f0ef48974a0d2524602fd5c44"},{"url":"https://git.kernel.org/stable/c/be00deee60044ffa820f9436415caeb665b2cda0"},{"url":"https://git.kernel.org/stable/c/9240fc1f2cde5331c61608da21b00394602ca762"},{"url":"https://git.kernel.org/stable/c/6d91041bb38b97e2feb625123cc0529d7b83a0e1"}],"tags":["cve.org"],"ingestedAt":"2026-10-18T15:45:12.248Z","slug":"CVE-2026-98600","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: RFCOMM: Reject short EA=0 frames in rfcomm_recv_frame()\n\nWhile rfcomm_recv_frame() verifies that skb->len is at least\nsizeof(*hdr) + 1 (4 bytes: 3-byte header + 1-byte FCS), an RFCOMM frame\nwith an extended 2-byte length field (!__test_ea(hdr->len)) has a 4-byte\nheader plus a 1-byte FCS (5 bytes minimum, sizeof(*hdr) + 2).\n\nWhen a 4-byte RFCOMM frame with EA == 0 arrives:\n1. The initial skb->len < sizeof(*hdr) + 1 check passes (4 < 4 is false).\n2. Trimming the FCS byte decrements skb->len to 3.\n3. If __check_fcs() succeeds, skb_pull(skb, 4) fails (4 > 3) and returns\n   NULL without advancing skb->data.\n4. Because the return value of skb_pull() is ignored, the un-pulled\n   3-byte struct rfcomm_hdr remains at skb->data and is either queued as\n   application payload via rfcomm_recv_data() or parsed as a multiplexer\n   control command via rfcomm_recv_mcc() on DLCI 0.\n\nFix this by extending the length check in rfcomm_recv_frame() to also\nrequire skb->len >= sizeof(*hdr) + 2 when !__test_ea(hdr->len).\n\n## Affected\n\n- `Linux >= fb40eda15122f6b780228639c1ead6820340ff54 < 76876fd26569302d26d91cbe8b75fa8e66cf8969`\n- `Linux >= 3829af5fab5a22405bf1e7d69068c2ec0fce46ca < 97711b964877242933484989224a3c4c5d88a5ee`\n- `Linux >= b161eacd7fa4a2d765724b5504ac6cc388e48f80 < 7a1781a2f3a9667b3065d402d1f11986a2363e08`\n- `Linux >= 30d1d9f3495463f7c026e4c553127f79b486fcd6 < c25587fa26761e623198b4f47151fe79d09ccde6`\n- `Linux >= 67dc3b40fae71b6b11c71e7ff69bac0758818c05 < 71ccacde407b7d8f0ef48974a0d2524602fd5c44`\n- `Linux >= bbc310caa2b6bf5fe42896ba27da0fbc12e4ac51 < be00deee60044ffa820f9436415caeb665b2cda0`\n- `Linux >= b230e5bf501c5edaf2eb0991cb862ac142031d4b < 9240fc1f2cde5331c61608da21b00394602ca762`\n- `Linux >= b230e5bf501c5edaf2eb0991cb862ac142031d4b < 6d91041bb38b97e2feb625123cc0529d7b83a0e1`\n- `Linux >= 6.12.111 < 6.12.112`\n- `Linux >= 6.18.53 < 6.18.55`\n- `Linux 7.2`\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":[]}