{"cve":"CVE-2026-74664","nvd":{"published":"2026-08-22T16:16:40.220","modified":"2026-10-14T13:10:00.187","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: openvswitch: reallocate update replies for mismatched IDs\n\novs_flow_cmd_new() preallocates the optional reply skb before it takes\novs_mutex and before it knows which existing flow will be updated.\n\nThat is normally fine because the skb is sized from the request flow\nidentifier.  That identifier also becomes the inserted flow's identifier.\nFor updates, however, a request with a UFID may miss the UFID lookup and\nthen fall back to the flow key lookup.  That lookup can legitimately find\nan existing key-identified flow.  UFIDs are optional and the flow key is\nthe primary identifier.\n\nFor echoed replies, ovs_flow_cmd_fill_info() writes the matched flow's\nidentifier, not the request identifier used for the preallocation.  A short\nrequest UFID can therefore leave too little room for the key identifier.\nThe fill can then fail with -EMSGSIZE and hit the BUG_ON(error < 0) in the\nupdate path.\n\nOnce the update target has been resolved, reallocate the reply skb if the\nmatched flow needs a larger reply than the request identifier allowed.  Do\nthis before replacing the actions so the request can still fail cleanly if\nthe rare extra allocation fails.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/00f987f066e802793a37dd2167459e67cf2cf2ec","https://git.kernel.org/stable/c/20751193d83be2e9735d4faee71375691c09cd13","https://git.kernel.org/stable/c/23716dd9d8d46a5908536b73dc085e62f2b5c237","https://git.kernel.org/stable/c/5d1c224dd914579524a183a514c12b95095d12ce","https://git.kernel.org/stable/c/696a0b9435fce9cf4f1e9ba7f6afa6bee96c97fc"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:49:38.260478770+00:00"},"epss":{"cve":"CVE-2026-74664","score":0.00177,"percentile":0.07159,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}