{"cve":"CVE-2026-55549","nvd":{"published":"2026-08-28T20:18:28.657","modified":"2026-09-08T21:08:37.320","status":"Awaiting Analysis","description":"Yamcs is a mission control framework. Prior to 5.9.4, Yamcs reflects an attacker-controlled redirect_uri parameter from GET /auth/authorize into yamcs-core/src/main/resources/auth/templates/authorize.html without adequate HTML escaping by yamcs-core/src/main/java/org/yamcs/http/auth/AuthHandler.java and yamcs-core/src/main/java/org/yamcs/http/HandlerContext.java. A crafted authorization URL can execute JavaScript when opened by a Yamcs user. The script can access browser-held authentication material and transmit it to an attacker, enabling account compromise. This issue is fixed in version 5.9.4.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N","score":6.5},"cwes":["CWE-79"],"references":["https://github.com/yamcs/yamcs/commit/4d47d5cdcf5d92c2c5bbbc19feada422923332e3","https://github.com/yamcs/yamcs/releases/tag/yamcs-5.9.4","https://github.com/yamcs/yamcs/security/advisories/GHSA-rxpg-wjf8-qv9c","https://github.com/yamcs/yamcs/security/advisories/GHSA-rxpg-wjf8-qv9c"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:50:50.842544443+00:00"},"epss":{"cve":"CVE-2026-55549","score":0.01305,"percentile":0.70541,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-rxpg-wjf8-qv9c","url":"https://osv.dev/vulnerability/GHSA-rxpg-wjf8-qv9c","summary":"Yamcs has Reflected XSS in the URL of the Authorize Endpoint","modified":"2026-08-28T17:40:35.523121Z","packages":[{"ecosystem":"Maven","name":"org.yamcs:yamcs-core","purl":"pkg:maven/org.yamcs/yamcs-core","ranges":["<5.9.4"],"fixed":["5.9.4"]}]}],"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."]}