{"id":"CVE-2026-40542","aliases":["GHSA-v468-qcjx-r72w"],"url":"https://o3.security/vulnerability/CVE-2026-40542","summary":"Apache HttpClient: SCRAM-SHA-256 mutual authentication bypass may cause the client to accept authentication without proper mutual authentication verification","details":"Missing critical step in authentication in Apache HttpClient 5.6 allows an attacker to cause the client to accept SCRAM-SHA-256 authentication without proper mutual authentication verification. Users are recommended to upgrade to version 5.6.1, which fixes this issue.","published":"2026-04-22T07:07:21.344Z","modified":"2026-09-11T03:30:58.619120190Z","cvss":{"score":7.3,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L"},"epss":{"score":0.00456,"percentile":0.3763,"asOf":"2026-08-24"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Maven","name":"org.apache.httpcomponents.client5:httpclient5","fixedVersion":"5.6.1"}],"fix":{"url":"https://github.com/apache/httpcomponents-client/commit/726eac2323d370435d8afca1e0540aa099927f18","label":"apache/httpcomponents-client@726eac2"},"references":[{"type":"WEB","url":"http://www.openwall.com/lists/oss-security/2026/04/22/5"},{"type":"WEB","url":"https://repo.maven.apache.org/maven2"},{"type":"WEB","url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-40542.json"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:60239"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:60246"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:60247"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:60248"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:60249"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:60250"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:60251"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:60252"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:60254"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:60256"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:60259"},{"type":"ADVISORY","url":"https://access.redhat.com/security/cve/CVE-2026-40542"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40542.json"},{"type":"ADVISORY","url":"https://lists.apache.org/thread/tfmgv86xr0z1y096vs3z0y315t1v3o97"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-40542"},{"type":"REPORT","url":"https://bugzilla.redhat.com/show_bug.cgi?id=2460518"},{"type":"WEB","url":"https://github.com/apache/httpcomponents-client/commit/726eac2323d370435d8afca1e0540aa099927f18"},{"type":"PACKAGE","url":"https://github.com/apache/httpcomponents-client"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-11T03:30:58.619120190Z"}}