{"id":"CVE-2026-81829","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-81829","generatedAt":"2026-10-28T04:37:36.533Z","title":"When the AWS_ALB key provider is configured, the resolver constructs the key-fetch URL by directly concatenating the attacker-controlled kid header value from an inbound JWT without sanitizing path traversal characters or query-string separators.","description":"A flaw was found in SmallRye JWT's AwsAlbKeyResolver, which is used by applications to verify JSON Web Tokens signed by AWS Application Load Balancers. When the AWS_ALB key provider is configured, the resolver constructs the key-fetch URL by directly concatenating the attacker-controlled kid header value from an inbound JWT without sanitizing path traversal characters or query-string separators. This allows an unauthenticated remote attacker to force the application server to issue GET requests to arbitrary paths on the same origin as the configured key endpoint. As a result, non-public endpoints or internal data reachable on that origin may be read by the attacker before JWT signature verification takes place.","published":"2026-09-17T14:17:32.000Z","lastModified":"2026-10-09T17:16:50.000Z","status":"Awaiting Analysis","sourceIdentifier":"secalert@redhat.com","cvss":{"version":"3.1","score":5.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N"},"cwe":["CWE-22"],"affected":[],"epss":{"score":0.0059,"percentile":0.48025,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.59%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://access.redhat.com/errata/RHSA-2026:69440","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:69470","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/security/cve/CVE-2026-81829","source":"secalert@redhat.com"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2524980","source":"secalert@redhat.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-81829","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}