{"id":"CVE-2021-47245","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: synproxy: Fix out of bounds when parsing TCP options\n\nThe TCP option parser in synproxy (synproxy_parse_options) could read\none byte out of bounds. When the length is 1, the execution flow gets\ninto the loop, reads one byte of the opcode, and if the opcode is\nneither TCPOPT_EOL nor TCPOPT_NOP, it reads one more byte, which exceeds\nthe length of 1.\n\nThis fix is inspired by commit 9609dad263f8 (\"ipv4: tcp_input: fix stack\nout of bounds when parsing TCP options.\").\n\nv2 changes:\n\nAdded an early return when length \u003c 0 to avoid calling\nskb_header_pointer with negative length.","modified":"2026-03-13T05:19:24.217796Z","published":"2024-05-21T15:15:13.550Z","related":["SUSE-SU-2024:1979-1","SUSE-SU-2024:1983-1","SUSE-SU-2024:2184-1"],"references":[{"type":"FIX","url":"https://git.kernel.org/stable/c/6defc77d48eff74075b80ad5925061b2fc010d98"},{"type":"FIX","url":"https://git.kernel.org/stable/c/7d9a9a1a88a3da574e019b4de756bc73337b3b0b"},{"type":"FIX","url":"https://git.kernel.org/stable/c/9cdf299ba4e153b5e56187648420de22c6216f02"},{"type":"FIX","url":"https://git.kernel.org/stable/c/e1eb98cfeafdd85537e7e3cefe93ca9bfbcc3ea8"},{"type":"FIX","url":"https://git.kernel.org/stable/c/f648089337cb8ed40b2bb96e244f72b9d97dc96b"},{"type":"FIX","url":"https://git.kernel.org/stable/c/576c1526b4d83c44ad7b673cb841f36cbc6cb6c4"},{"type":"FIX","url":"https://git.kernel.org/stable/c/5fc177ab759418c9537433e63301096e733fb915"},{"type":"FIX","url":"https://git.kernel.org/stable/c/674b5f0c6a4fc5d3abce877048290cea6091fcb1"}],"affected":[{"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2021-47245.json","unresolved_ranges":[{"events":[{"introduced":"3.12"},{"fixed":"4.4.274"}]},{"events":[{"introduced":"4.5"},{"fixed":"4.9.274"}]},{"events":[{"introduced":"4.10"},{"fixed":"4.14.238"}]},{"events":[{"introduced":"4.15"},{"fixed":"4.19.196"}]},{"events":[{"introduced":"4.20"},{"fixed":"5.4.128"}]},{"events":[{"introduced":"5.5"},{"fixed":"5.10.46"}]},{"events":[{"introduced":"5.11"},{"fixed":"5.12.13"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc1"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc2"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc3"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc4"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc5"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc6"}]}]}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H"}]}