{"cve":"CVE-2026-40542","nvd":{"published":"2026-04-22T08:16:12.780","modified":"2026-10-26T21:10:00.170","status":"Modified","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L","score":7.3},"cwes":["CWE-304","CWE-325"],"references":["https://lists.apache.org/thread/tfmgv86xr0z1y096vs3z0y315t1v3o97","http://www.openwall.com/lists/oss-security/2026/04/22/5","https://access.redhat.com/errata/RHSA-2026:60239","https://access.redhat.com/errata/RHSA-2026:60246","https://access.redhat.com/errata/RHSA-2026:60247"],"products":["apache:httpclient"],"source":"nvd","synced_at":"2026-10-26T21:38:48.864438205+00:00"},"epss":{"cve":"CVE-2026-40542","score":0.00536,"percentile":0.44941,"date":"2026-10-26"},"kev":null,"osv":[{"id":"GHSA-v468-qcjx-r72w","url":"https://osv.dev/vulnerability/GHSA-v468-qcjx-r72w","summary":"Apache HttpClient accepts SCRAM-SHA-256 authentication without proper mutual authentication verification","modified":"2026-09-10T03:51:03.206251606Z","packages":[{"ecosystem":"Maven","name":"org.apache.httpcomponents.client5:httpclient5","purl":"pkg:maven/org.apache.httpcomponents.client5/httpclient5","ranges":[">=5.6-alpha1 <5.6.1"],"fixed":["5.6.1"]}]}],"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."]}