{"id":"CVE-2026-80255","state":"PUBLISHED","title":"secure cookie attribute bypass with tab","description":"A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of\nspace (ascii code 32) immediately before the `Secure` attribute causes curl to\nstore the cookie without its Secure flag. The cookie might then wrongfully be\nsent over plaintext HTTP on subsequent requests to the same host.","publishedAt":"2026-09-06T17:48:54.275Z","updatedAt":"2026-09-15T06:03:13.400Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","source":"CISA-ADP"},"assigner":"curl","products":["curl curl"],"affected":[{"vendor":"curl","product":"curl","defaultStatus":"unaffected","versions":[{"version":"8.13.0","status":"affected","lessThan":"8.14.2","versionType":"semver"},{"version":"8.15.0","status":"affected","lessThan":"8.16.1","versionType":"semver"},{"version":"8.17.0","status":"affected","lessThan":"8.20.1","versionType":"semver"},{"version":"8.21.0","status":"affected","lessThan":"8.22.0","versionType":"semver"}]},{"vendor":"curl","product":"curl","defaultStatus":"unaffected","versions":[{"version":"1aea05a6c2699e80c75936d58569851555acd603","status":"affected","lessThan":"4f6aa41a0145e930e766775dbe860883d350aa0a","versionType":"git"}],"repo":"https://github.com/curl/curl.git"},{"vendor":"curl","product":"curl","defaultStatus":"unaffected","versions":[{"version":"8.21.0","status":"affected"},{"version":"8.20.0","status":"affected"},{"version":"8.19.0","status":"affected"},{"version":"8.18.0","status":"affected"},{"version":"8.17.0","status":"affected"},{"version":"8.16.0","status":"affected"},{"version":"8.15.0","status":"affected"},{"version":"8.14.1","status":"affected"},{"version":"8.14.0","status":"affected"},{"version":"8.13.0","status":"affected"}]}],"references":["https://curl.se/docs/CVE-2026-80255.json","https://curl.se/docs/CVE-2026-80255.html","https://hackerone.com/reports/3972395"],"weaknesses":["CWE-201"],"ingestedAt":"2026-10-29T20:13:07.220Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/80xxx/CVE-2026-80255.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-80255","state":"PUBLISHED","datePublished":"2026-09-06T17:48:54.275Z","dateUpdated":"2026-09-15T06:03:13.400Z","assignerShortName":"curl","assignerOrgId":"2499f714-1537-4658-8207-48ae4bb9eae9","dateReserved":"2026-08-26T06:25:58.220Z"},"containers":{"cna":{"title":"secure cookie attribute bypass with tab","descriptions":[{"lang":"en","value":"A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of\nspace (ascii code 32) immediately before the `Secure` attribute causes curl to\nstore the cookie without its Secure flag. The cookie might then wrongfully be\nsent over plaintext HTTP on subsequent requests to the same host."}],"affected":[{"vendor":"curl","product":"curl","defaultStatus":"unaffected","versions":[{"version":"8.13.0","status":"affected","lessThan":"8.14.2","versionType":"semver"},{"version":"8.15.0","status":"affected","lessThan":"8.16.1","versionType":"semver"},{"version":"8.17.0","status":"affected","lessThan":"8.20.1","versionType":"semver"},{"version":"8.21.0","status":"affected","lessThan":"8.22.0","versionType":"semver"}]},{"vendor":"curl","product":"curl","defaultStatus":"unaffected","versions":[{"version":"1aea05a6c2699e80c75936d58569851555acd603","status":"affected","lessThan":"4f6aa41a0145e930e766775dbe860883d350aa0a","versionType":"git"}],"repo":"https://github.com/curl/curl.git"},{"vendor":"curl","product":"curl","defaultStatus":"unaffected","versions":[{"version":"8.21.0","status":"affected"},{"version":"8.20.0","status":"affected"},{"version":"8.19.0","status":"affected"},{"version":"8.18.0","status":"affected"},{"version":"8.17.0","status":"affected"},{"version":"8.16.0","status":"affected"},{"version":"8.15.0","status":"affected"},{"version":"8.14.1","status":"affected"},{"version":"8.14.0","status":"affected"},{"version":"8.13.0","status":"affected"}]}],"references":[{"url":"https://curl.se/docs/CVE-2026-80255.json"},{"url":"https://curl.se/docs/CVE-2026-80255.html"},{"url":"https://hackerone.com/reports/3972395"}],"problemTypes":[{"descriptions":[{"cweId":"CWE-201","lang":"en","description":"Information Exposure Through Sent Data","type":"CWE"}]}],"providerMetadata":{"shortName":"curl","orgId":"2499f714-1537-4658-8207-48ae4bb9eae9","dateUpdated":"2026-09-15T06:03:13.400Z"},"x_osv":{"schema_version":"1.5.0","id":"CURL-CVE-2026-80255","aliases":["CVE-2026-80255"],"summary":"secure cookie attribute bypass with tab","modified":"2026-09-07T10:34:51.00Z","database_specific":{"package":"curl","affects":"both","URL":"https://curl.se/docs/CVE-2026-80255.json","www":"https://curl.se/docs/CVE-2026-80255.html","issue":"https://hackerone.com/reports/3972395","CWE":{"id":"CWE-201","desc":"Information Exposure Through Sent Data"},"last_affected":"8.21.0","severity":"Low"},"published":"2026-09-02T08:00:00.00Z","affected":[{"ranges":[{"type":"SEMVER","events":[{"introduced":"8.13.0"},{"fixed":"8.14.2"},{"introduced":"8.15.0"},{"fixed":"8.16.1"},{"introduced":"8.17.0"},{"fixed":"8.20.1"},{"introduced":"8.21.0"},{"fixed":"8.22.0"}]},{"type":"GIT","repo":"https://github.com/curl/curl.git","events":[{"introduced":"1aea05a6c2699e80c75936d58569851555acd603"},{"fixed":"4f6aa41a0145e930e766775dbe860883d350aa0a"}]}],"versions":["8.21.0","8.20.0","8.19.0","8.18.0","8.17.0","8.16.0","8.15.0","8.14.1","8.14.0","8.13.0"]}],"credits":[{"name":"Stanislav Fort (Aisle Research)","type":"finder"},{"name":"Daniel Stenberg","type":"remediation developer"}],"details":"A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of\nspace (ascii code 32) immediately before the `Secure` attribute causes curl to\nstore the cookie without its Secure flag. The cookie might then wrongfully be\nsent over plaintext HTTP on subsequent requests to the same host."},"credits":[{"lang":"en","value":"Stanislav Fort (Aisle Research)","type":"finder"},{"lang":"en","value":"Daniel Stenberg","type":"remediation developer"}],"x_generator":{"engine":"cvelib 1.8.0"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://hackerone.com/reports/3972395","tags":["exploit"]}],"metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":7.5,"attackVector":"NETWORK","baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","integrityImpact":"NONE","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"NONE","privilegesRequired":"NONE","confidentialityImpact":"HIGH"}},{"other":{"type":"ssvc","content":{"timestamp":"2026-09-08T18:45:09.883106Z","id":"CVE-2026-80255","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-201","type":"CWE","lang":"en","description":"CWE-201 Insertion of Sensitive Information Into Sent Data"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-08T18:45:49.180Z"}}]}}}