{"id":"GHSA-c3m8-x3cg-qm2c","aliases":[],"status":"published","title":"Configuration Override in helmet-csp","description":"Versions of `helmet-csp` before to 2.9.1 are vulnerable to a Configuration Override affecting the application's Content Security Policy (CSP). The package's browser sniffing for Firefox deletes the `default-src` CSP policy, which is the fallback policy. This allows an attacker to remove an application's default CSP, possibly rendering the application vulnerable to Cross-Site Scripting.\n\n\n## Recommendation\n\nUpgrade to version 2.9.1 or later. Setting the `browserSniff` configuration to `false` in vulnerable versions also mitigates the issue.","severity":{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium","from":"ghsa"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"published":"2020-09-03T20:39:53Z","modified":"2023-01-09T05:04:08Z","fixes":[{"ecosystem":"npm","package":"helmet-csp","fixed_in":["2.9.1"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"helmet-csp","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"1.2.2"},{"fixed":"2.9.1"}]}]},{"source":"osv","ecosystem":"npm","package":"helmet-csp","ranges":[{"type":"SEMVER","events":[{"introduced":"1.2.2"},{"fixed":"2.9.1"}]}]}],"references":[{"url":"https://www.npmjs.com/advisories/1176","tags":["web"]},{"url":"https://github.com/helmetjs/csp/commit/67a69baafa8198a154f0505a0cf0875f76f6186a","tags":["web"]},{"url":"https://snyk.io/vuln/SNYK-JS-HELMETCSP-469436","tags":["web"]},{"url":"https://github.com/advisories/GHSA-c3m8-x3cg-qm2c"},{"url":"https://github.com/helmetjs/csp","tags":["web"]}],"sources":{"ghsa":[{"id":"GHSA-c3m8-x3cg-qm2c","title":"Configuration Override in helmet-csp","description":"Versions of `helmet-csp` before to 2.9.1 are vulnerable to a Configuration Override affecting the application's Content Security Policy (CSP). The package's browser sniffing for Firefox deletes the `default-src` CSP policy, which is the fallback policy. This allows an attacker to remove an application's default CSP, possibly rendering the application vulnerable to Cross-Site Scripting.\n\n\n## Recommendation\n\nUpgrade to version 2.9.1 or later. Setting the `browserSniff` configuration to `false` in vulnerable versions also mitigates the issue.","status":"published","published":"2020-09-03T20:39:53Z","modified":"2023-01-09T05:04:08Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T14:36:08.863482Z"}],"osv":[{"id":"GHSA-c3m8-x3cg-qm2c","title":"Configuration Override in helmet-csp","description":"Versions of `helmet-csp` before to 2.9.1 are vulnerable to a Configuration Override affecting the application's Content Security Policy (CSP). The package's browser sniffing for Firefox deletes the `default-src` CSP policy, which is the fallback policy. This allows an attacker to remove an application's default CSP, possibly rendering the application vulnerable to Cross-Site Scripting.\n\n\n## Recommendation\n\nUpgrade to version 2.9.1 or later. Setting the `browserSniff` configuration to `false` in vulnerable versions also mitigates the issue.","status":"published","published":"2020-09-03T20:39:53Z","modified":"2021-09-29T18:45:07Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:46:44.571161Z"}]}}