{"id":"AZL-111203","summary":"CVE-2026-99112 affecting package kernel 6.6.157.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: cls_flower: validate mask pointer after nla_next()\n\nfl_set_enc_opt() iterates the key's nested tunnel-option attributes\nwith nla_for_each_attr() while advancing a single mask pointer via\nnla_next() at the bottom of each loop, so the mask cursor is driven\nby the number of key attributes rather than by the mask's own\nattributes.  The nla_ok() added by commit c96adff956191 (\"cls_flower:\ncall nla_ok() before nla_next()\") only validates the mask pointer\nthat was just consumed; the pointer produced by nla_next() is used by\nthe next iteration (fl_set_geneve_opt() and siblings) without any\nvalidation.\n\nThe mask's nested attributes are validated with NL_VALIDATE_LIBERAL,\nwhich merely warns on trailing bytes that do not form a complete\nattribute.  A mask carrying one valid attribute plus 1-3 residue\nbytes (or a non-aligned attribute length making msk_depth negative)\ntherefore reaches the next iteration with msk_depth != 0, so neither\nthe !msk_depth check in fl_set_enc_opt() nor the !depth check in the\nper-type helpers fires.  nla_type() then reads past the mask payload\nand nla_parse_nested_deprecated() iterates with an nla_len taken\nfrom those bytes, reading well beyond the mask attribute (KASAN:\nslab-out-of-bounds read in __nla_validate_parse from fl_change()).\n\nValidate the advanced mask pointer as well: when the mask is not\nlegitimately exhausted (msk_depth != 0) and the new pointer fails\nnla_ok(), reject the filter with -EINVAL.  An exactly exhausted mask\nstill skips the check, preserving exact-match behaviour for the\nremaining key attributes.","modified":"2026-10-29T14:16:53.999218070Z","published":"2026-10-28T11:17:30Z","upstream":["CVE-2026-99112"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-99112"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"6.6.157.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-111203.json"}}],"schema_version":"1.9.2"}