{"cve":"CVE-2026-31430","nvd":{"published":"2026-04-20T10:16:16.877","modified":"2026-06-17T10:33:42.270","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nX.509: Fix out-of-bounds access when parsing extensions\n\nLeo reports an out-of-bounds access when parsing a certificate with\nempty Basic Constraints or Key Usage extension because the first byte of\nthe extension is read before checking its length.  Fix it.\n\nThe bug can be triggered by an unprivileged user by submitting a\nspecially crafted certificate to the kernel through the keyrings(7) API.\nLeo has demonstrated this with a proof-of-concept program responsibly\ndisclosed off-list.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","score":7.1},"cwes":["CWE-125"],"references":["https://git.kernel.org/stable/c/206121294b9cf27f0589857f80d64f87e496ffb2","https://git.kernel.org/stable/c/30ab358fad0c7daa1d282ec48089901b21b36a20","https://git.kernel.org/stable/c/672b526def1f94c1be8eb11b885b803da0d8c2f1","https://git.kernel.org/stable/c/7fb4dadc2734f4020d7543d688b8d49c8e569c61","https://git.kernel.org/stable/c/d702c3408213bb12bd570bb97204d8340d141c51"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:30:49.762551342+00:00"},"epss":{"cve":"CVE-2026-31430","score":0.00081,"percentile":0.00161,"date":"2026-10-31"},"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."]}