{"id":"CVE-2026-34206","state":"PUBLISHED","title":"Captcha Protect: Reflected XSS in challenge page via unsanitized destination rendered with text/template","description":"Captcha Protect is a Traefik middleware to add an anti-bot challenge to individual IPs in a subnet when traffic spikes are detected from that subnet. Prior to version 1.12.2, a reflected cross-site scripting (XSS) vulnerability exists in github.com/libops/captcha-protect. The challenge page accepted a client-supplied destination value and rendered it into HTML using Go's text/template. Because text/template does not perform contextual HTML escaping, an attacker could supply a crafted destination value that breaks out of the hidden input attribute and injects arbitrary script into the challenge page. This issue has been patched in version 1.12.2.","publishedAt":"2026-03-31T19:34:21.383Z","updatedAt":"2026-04-01T18:41:05.256Z","severity":{"score":6.1,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["libops captcha-protect"],"affected":[{"vendor":"libops","product":"captcha-protect","versions":[{"version":"< 1.12.2","status":"affected"}]}],"references":["https://github.com/libops/captcha-protect/security/advisories/GHSA-ph62-4j5g-2q4r","https://github.com/libops/captcha-protect/commit/eef6211ecd1147273be484d913b81c68c0bd8d3f","https://github.com/libops/captcha-protect/releases/tag/v1.12.2"],"weaknesses":["CWE-79"],"ingestedAt":"2026-10-29T20:11:40.391Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/34xxx/CVE-2026-34206.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-34206","state":"PUBLISHED","datePublished":"2026-03-31T19:34:21.383Z","dateUpdated":"2026-04-01T18:41:05.256Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-03-26T15:57:52.323Z"},"containers":{"cna":{"title":"Captcha Protect: Reflected XSS in challenge page via unsanitized destination rendered with text/template","descriptions":[{"lang":"en","value":"Captcha Protect is a Traefik middleware to add an anti-bot challenge to individual IPs in a subnet when traffic spikes are detected from that subnet. Prior to version 1.12.2, a reflected cross-site scripting (XSS) vulnerability exists in github.com/libops/captcha-protect. The challenge page accepted a client-supplied destination value and rendered it into HTML using Go's text/template. Because text/template does not perform contextual HTML escaping, an attacker could supply a crafted destination value that breaks out of the hidden input attribute and injects arbitrary script into the challenge page. This issue has been patched in version 1.12.2."}],"affected":[{"vendor":"libops","product":"captcha-protect","versions":[{"version":"< 1.12.2","status":"affected"}]}],"references":[{"url":"https://github.com/libops/captcha-protect/security/advisories/GHSA-ph62-4j5g-2q4r","name":"https://github.com/libops/captcha-protect/security/advisories/GHSA-ph62-4j5g-2q4r","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/libops/captcha-protect/commit/eef6211ecd1147273be484d913b81c68c0bd8d3f","name":"https://github.com/libops/captcha-protect/commit/eef6211ecd1147273be484d913b81c68c0bd8d3f","tags":["x_refsource_MISC"]},{"url":"https://github.com/libops/captcha-protect/releases/tag/v1.12.2","name":"https://github.com/libops/captcha-protect/releases/tag/v1.12.2","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":6.1,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","integrityImpact":"LOW","privilegesRequired":"NONE","scope":"CHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-79","lang":"en","description":"CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-03-31T19:34:21.383Z"},"source":{"advisory":"GHSA-ph62-4j5g-2q4r","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-04-01T18:40:57.202868Z","id":"CVE-2026-34206","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-04-01T18:41:05.256Z"}}]}}}