{"id":"CVE-2026-80603","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_conntrack_irc: fix parse_dcc() off-by-one OOB read\n\nparse_dcc() treats data_end as an inclusive end pointer, but its only\ncaller passes data_limit = ib_pt…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_conntrack_irc: fix parse_dcc() off-by-one OOB read\n\nparse_dcc() treats data_end as an inclusive end pointer, but its only\ncaller passes data_limit = ib_pt…","severity":"critical","cvss":9.1,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","cwe":["CWE-193"],"vendor":"Linux","product":"Linux","affected":["Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < abb8c32b88ea3f46beb68c34fe9a3ac8ed664e7e","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 437e0a3854b3a44ec15afa9ab88ec215adf3a2fd","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 910c33e4a8c046c3cc1fa5a465a4d41a1bb398f1","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 2b70f61f569bb29acb380e6f616a1bbdee15668f","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 2393f0bd7a467ad475598f3a5b9de27ca36e3037","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < aff589556ed772cb1c0c2d7b4d91ec45c0c39416","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < eeef3b81f449560653662df2dde6f6fe247c5365","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < ef6400ca25a13fd6dedbe8ef4a1d0979bbbfe88a","Linux 2.6.12"],"published":"2026-08-28","updated":"2026-10-16","sourceUpdated":"2026-10-16T20:18:03.287","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-80603","references":[{"url":"https://git.kernel.org/stable/c/2393f0bd7a467ad475598f3a5b9de27ca36e3037","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/2b70f61f569bb29acb380e6f616a1bbdee15668f","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/437e0a3854b3a44ec15afa9ab88ec215adf3a2fd","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/910c33e4a8c046c3cc1fa5a465a4d41a1bb398f1","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/abb8c32b88ea3f46beb68c34fe9a3ac8ed664e7e","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/aff589556ed772cb1c0c2d7b4d91ec45c0c39416","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/eeef3b81f449560653662df2dde6f6fe247c5365","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ef6400ca25a13fd6dedbe8ef4a1d0979bbbfe88a","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80603.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-80603"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2525369"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-80603"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-80603"},{"url":"https://kernelcve.org/list/?q=CVE-2026-80603"},{"url":"https://lore.kernel.org/linux-cve-announce/2026082832-CVE-2026-80603-872e@gregkh/T"}],"tags":["nvd","cve.org","csaf","vex","red-hat","score-dispute"],"epss":0.00595,"epssPercentile":0.48242,"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"total","timestamp":"2026-10-16T19:18:30.666759Z"},"scores":{"nvd":9.1,"vendor":5.3},"ingestedAt":"2026-08-29T22:43:16.073Z","slug":"CVE-2026-80603","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_conntrack_irc: fix parse_dcc() off-by-one OOB read\n\nparse_dcc() treats data_end as an inclusive end pointer, but its only\ncaller passes data_limit = ib_ptr + datalen, which points one past the\nlast valid byte.\n\nThe newline search loop iterates while tmp <= data_end, so when no\nnewline is present, *tmp is read at tmp == data_end, one byte beyond\nthe region filled by skb_header_pointer().\n\nirc_buffer is kmalloc'd as MAX_SEARCH_SIZE + 1 bytes and datalen is\ncapped at MAX_SEARCH_SIZE, so the stray read does not fault.  The byte\nis uninitialized or stale; if it contains an ASCII digit, simple_strtoul\nwill consume it and produce a wrong DCC IP or port in the conntrack\nexpectation.  The extra allocation byte is also a fragile guard: if the\ncap or allocation size changes, this becomes a real out-of-bounds read.\n\nChange the loop and its post-loop check to use strict less-than,\nconsistent with the caller's exclusive-end convention.  Update the\nfunction comment accordingly.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, … · updated 2026-10-24 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80603.json)","depth":"midnight","depthScore":50,"depthScoreParts":{"impact":50.1,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}