{"id":"CVE-2026-55891","state":"PUBLISHED","title":"PrivateBin: Reflected JSON injection in backend responses via unescaped REQUEST_URI","description":"PrivateBin is an online pastebin where the server has zero knowledge of pasted data. Prior to 2.0.5, Request::getRequestUri() in lib/Request.php passes $_SERVER['REQUEST_URI'] through FILTER_SANITIZE_URL, which does not remove quotation marks, angle brackets, or apostrophes, and Controller::_init() stores the attacker-controlled value in Controller::$_urlBase. Controller::_jsonld() in lib/Controller.php then uses str_replace() to insert that value without JSON escaping into js/types.jsonld, js/paste.jsonld, and the other JSON-LD templates used by /?jsonld= and /?pasteid. A raw quotation mark delivered by an HTTP client, proxy, or structured-data crawler that does not normalize the request target can break out of the JSON string and inject arbitrary key-value data into a CORS-open application/ld+json response. The jsonld branch in Controller::__construct() returns before _setCacheHeaders(), so the response also lacks X-Content-Type-Options: nosniff, Content Security Policy, X-Frame-Options, and Referrer-Policy. Direct script execution was not demonstrated, but manipulated responses can affect structured-data consumers or combine with less strict clients. This issue is fixed in version 2.0.5.","publishedAt":"2026-08-28T20:23:50.477Z","updatedAt":"2026-08-31T18:47:39.096Z","severity":{"score":0,"label":"None","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["PrivateBin PrivateBin"],"affected":[{"vendor":"PrivateBin","product":"PrivateBin","versions":[{"version":"< 2.0.5","status":"affected"}]}],"references":["https://github.com/PrivateBin/PrivateBin/security/advisories/GHSA-xrjc-c68j-hp7w","https://github.com/PrivateBin/PrivateBin/commit/164c839c39688533ef0086575878e8392cd21249","https://github.com/PrivateBin/PrivateBin/releases/tag/2.0.5"],"weaknesses":["CWE-116"],"ingestedAt":"2026-10-29T20:12:24.861Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/55xxx/CVE-2026-55891.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-55891","state":"PUBLISHED","datePublished":"2026-08-28T20:23:50.477Z","dateUpdated":"2026-08-31T18:47:39.096Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-06-17T16:59:42.760Z"},"containers":{"cna":{"title":"PrivateBin: Reflected JSON injection in backend responses via unescaped REQUEST_URI","descriptions":[{"lang":"en","value":"PrivateBin is an online pastebin where the server has zero knowledge of pasted data. Prior to 2.0.5, Request::getRequestUri() in lib/Request.php passes $_SERVER['REQUEST_URI'] through FILTER_SANITIZE_URL, which does not remove quotation marks, angle brackets, or apostrophes, and Controller::_init() stores the attacker-controlled value in Controller::$_urlBase. Controller::_jsonld() in lib/Controller.php then uses str_replace() to insert that value without JSON escaping into js/types.jsonld, js/paste.jsonld, and the other JSON-LD templates used by /?jsonld= and /?pasteid. A raw quotation mark delivered by an HTTP client, proxy, or structured-data crawler that does not normalize the request target can break out of the JSON string and inject arbitrary key-value data into a CORS-open application/ld+json response. The jsonld branch in Controller::__construct() returns before _setCacheHeaders(), so the response also lacks X-Content-Type-Options: nosniff, Content Security Policy, X-Frame-Options, and Referrer-Policy. Direct script execution was not demonstrated, but manipulated responses can affect structured-data consumers or combine with less strict clients. This issue is fixed in version 2.0.5."}],"affected":[{"vendor":"PrivateBin","product":"PrivateBin","versions":[{"version":"< 2.0.5","status":"affected"}]}],"references":[{"url":"https://github.com/PrivateBin/PrivateBin/security/advisories/GHSA-xrjc-c68j-hp7w","name":"https://github.com/PrivateBin/PrivateBin/security/advisories/GHSA-xrjc-c68j-hp7w","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/PrivateBin/PrivateBin/commit/164c839c39688533ef0086575878e8392cd21249","name":"https://github.com/PrivateBin/PrivateBin/commit/164c839c39688533ef0086575878e8392cd21249","tags":["x_refsource_MISC"]},{"url":"https://github.com/PrivateBin/PrivateBin/releases/tag/2.0.5","name":"https://github.com/PrivateBin/PrivateBin/releases/tag/2.0.5","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":0,"baseSeverity":"NONE","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-116","lang":"en","description":"CWE-116: Improper Encoding or Escaping of Output","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-08-28T20:23:50.477Z"},"source":{"advisory":"GHSA-xrjc-c68j-hp7w","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/PrivateBin/PrivateBin/security/advisories/GHSA-xrjc-c68j-hp7w","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-31T18:47:12.873010Z","id":"CVE-2026-55891","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-31T18:47:39.096Z"}}]}}}