{"id":"CVE-2026-98969","revision":"2c5d42147d6143669a7d780641d71568","records":[{"revision":"2c5d42147d6143669a7d780641d71568","observedAt":"2026-10-23T16:01:20.601+00:00","statement":{"source":"cve-program","id":"CVE-2026-98969","aliases":[],"title":"net/sched: em_text: reject unterminated algo before autoload","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: em_text: reject unterminated algo before autoload\n\nThis is a follow-up to commit 9c572a83037a (\"net/sched: fix potential\nstack infoleak in em_text_dump()\"), which zero-initialised the dump-side\nstruct. Sashiko pointed at a pre-existing bug that exposed the change-side\ninput-validation gap open.\n\nem_text_change() casts the raw netlink attribute payload to struct\ntcf_em_text and passes conf->algo, a 16-byte array with no enforced NUL\nterminator, to textsearch_prepare().  On the TS_AUTOLOAD retry\ntextsearch_prepare() calls request_module(\"ts_%s\", algo); vsnprintf()\nwalks %s until it finds a NUL, so an algo[] with no NUL reads past the\narray into the adjacent struct fields and payload and feeds those bytes\nto the usermode helper command line.  This is an out-of-bounds read and\na kernel memory disclosure.\n\nReject the attribute when no NUL exists within TC_EM_TEXT_ALGOSIZ bytes,\nmatching the check xt_string has had since 3ab720881b6e.\n\nConditions to recreate the bug:\n- CAP_NET_ADMIN on the target netns (namespace-local via unshare -Urn\n  is enough)\n- install clsact on an interface, then add a basic filter with one text\n  ematch whose algo[] is 16 bytes with no NUL (e.g. \"A\"*16) and\n  pattern_len at least 1\n- the add fails with -ENOENT and the kernel invokes modprobe with a\n  module name made of \"ts_\" plus the 16 bytes and the adjacent payload","state":0,"publishedAt":"2026-10-23T12:19:42.012+00:00","modifiedAt":"2026-10-23T12:19:42.012+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/sched/em_text.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"d675c989ed2d4ba23dff615330b04371aea83534\",\n                            \"lessThan\": \"00bcc303000bac524d62eed054d77372b38ace0f\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"d675c989ed2d4ba23dff615330b04371aea83534\",\n                            \"lessThan\": \"22182f91c6703af6e9832cffe6d22b381031cb5a\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"d675c989ed2d4ba23dff615330b04371aea83534\",\n                            \"lessThan\": \"85e5512369d4fe6e5f2c43712d9f9e01d4ae8437\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"d675c989ed2d4ba23dff615330b04371aea83534\",\n                            \"lessThan\": \"b627c6ba20be20334338229b4820baacb9d96826\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"d675c989ed2d4ba23dff615330b04371aea83534\",\n                            \"lessThan\": \"c9728fcf2e7fb4a7a8d08ebd9524c3b02ae1a021\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/sched/em_text.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"2.6.13\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"2.6.13\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.160\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.113\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.57\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.11\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/00bcc303000bac524d62eed054d77372b38ace0f","https://git.kernel.org/stable/c/22182f91c6703af6e9832cffe6d22b381031cb5a","https://git.kernel.org/stable/c/85e5512369d4fe6e5f2c43712d9f9e01d4ae8437","https://git.kernel.org/stable/c/b627c6ba20be20334338229b4820baacb9d96826","https://git.kernel.org/stable/c/c9728fcf2e7fb4a7a8d08ebd9524c3b02ae1a021"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98969","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-98969","identifiers":["CVE-2026-98969"]},"retained":false,"historicalAffected":[]}],"coverage":[]}