{"api_version":"1","generated_at":"2026-08-19T11:45:16+00:00","cve":"CVE-2026-72889","urls":{"html":"https://cve.report/CVE-2026-72889","api":"https://cve.report/api/cve/CVE-2026-72889.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-72889","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-72889"},"summary":{"title":"Net::OAuth versions before 0.33 for Perl allow the sender to choose the signature algorithm in verify","description":"Net::OAuth versions before 0.33 for Perl allow the sender to choose the signature algorithm in verify.\n\nverify resolves the signature method class from the signature_method parameter of the incoming message. signature_method is required on every request, so the algorithm used to check a signature is chosen by whoever sent it, and nothing lets the verifying party pin the method instead. When a message names HMAC-SHA1 or HMAC-SHA256, the key is derived from consumer_secret and token_secret rather than from the key the provider deployed.\n\nA provider deployed on RSA-SHA1 holds only the consumer public key, and RFC 5849 does not use consumer_secret for that method, so the required parameter is filled with a placeholder. A client that names HMAC-SHA1 instead has its signature checked against that placeholder, so a guessable one is enough to forge requests for any consumer key and token.","state":"PUBLISHED","assigner":"CPANSec","published_at":"2026-08-19 08:17:13","updated_at":"2026-08-19 08:17:13"},"problem_types":["CWE-347","CWE-757","CWE-347 CWE-347 Improper Verification of Cryptographic Signature","CWE-757 CWE-757 Selection of Less-Secure Algorithm During Negotiation ('Algorithm Downgrade')"],"metrics":[],"references":[{"url":"https://github.com/vurtdev/Net-OAuth/commit/c467adf45c8d77ac4b92ad78b3eebf949252ba7f.patch","name":"https://github.com/vurtdev/Net-OAuth/commit/c467adf45c8d77ac4b92ad78b3eebf949252ba7f.patch","refsource":"9b29abf9-4ab0-4765-b253-1875cd9b441e","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/vurtdev/Net-OAuth/security/advisories/GHSA-c8rm-g5cm-4pf5","name":"https://github.com/vurtdev/Net-OAuth/security/advisories/GHSA-c8rm-g5cm-4pf5","refsource":"9b29abf9-4ab0-4765-b253-1875cd9b441e","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://metacpan.org/release/RRWO/Net-OAuth-0.33/changes","name":"https://metacpan.org/release/RRWO/Net-OAuth-0.33/changes","refsource":"9b29abf9-4ab0-4765-b253-1875cd9b441e","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://datatracker.ietf.org/doc/html/rfc5849#section-3.4.2","name":"https://datatracker.ietf.org/doc/html/rfc5849#section-3.4.2","refsource":"9b29abf9-4ab0-4765-b253-1875cd9b441e","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://datatracker.ietf.org/doc/html/rfc5849#section-3.4.3","name":"https://datatracker.ietf.org/doc/html/rfc5849#section-3.4.3","refsource":"9b29abf9-4ab0-4765-b253-1875cd9b441e","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-72889","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-72889","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[],"timeline":[],"solutions":[{"source":"CNA","title":"","value":"Upgrade to Net-OAuth 0.33 or later.","time":"","lang":"en"}],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"collectionURL":"https://cpan.org/modules","defaultStatus":"unaffected","modules":["Net::OAuth"],"packageName":"Net-OAuth","packageURL":"pkg:cpan/Net-OAuth","programFiles":["lib/Net/OAuth/Message.pm","lib/Net/OAuth/Request.pm"],"programRoutines":[{"name":"Net::OAuth::Message::verify"},{"name":"Net::OAuth::Message::_signature_method_class"},{"name":"Net::OAuth::Request::signature_key"}],"repo":"https://github.com/vurtdev/Net-OAuth","versions":[{"lessThan":"0.33","status":"affected","version":"0","versionType":"custom"}]}],"descriptions":[{"lang":"en","value":"Net::OAuth versions before 0.33 for Perl allow the sender to choose the signature algorithm in verify.\n\nverify resolves the signature method class from the signature_method parameter of the incoming message. signature_method is required on every request, so the algorithm used to check a signature is chosen by whoever sent it, and nothing lets the verifying party pin the method instead. When a message names HMAC-SHA1 or HMAC-SHA256, the key is derived from consumer_secret and token_secret rather than from the key the provider deployed.\n\nA provider deployed on RSA-SHA1 holds only the consumer public key, and RFC 5849 does not use consumer_secret for that method, so the required parameter is filled with a placeholder. A client that names HMAC-SHA1 instead has its signature checked against that placeholder, so a guessable one is enough to forge requests for any consumer key and token."}],"problemTypes":[{"descriptions":[{"cweId":"CWE-347","description":"CWE-347 Improper Verification of Cryptographic Signature","lang":"en","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-757","description":"CWE-757 Selection of Less-Secure Algorithm During Negotiation ('Algorithm Downgrade')","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-08-19T07:20:09.095Z","orgId":"9b29abf9-4ab0-4765-b253-1875cd9b441e","shortName":"CPANSec"},"references":[{"tags":["vendor-advisory"],"url":"https://github.com/vurtdev/Net-OAuth/security/advisories/GHSA-c8rm-g5cm-4pf5"},{"tags":["patch"],"url":"https://github.com/vurtdev/Net-OAuth/commit/c467adf45c8d77ac4b92ad78b3eebf949252ba7f.patch"},{"tags":["release-notes"],"url":"https://metacpan.org/release/RRWO/Net-OAuth-0.33/changes"},{"tags":["technical-description"],"url":"https://datatracker.ietf.org/doc/html/rfc5849#section-3.4.2"},{"tags":["technical-description"],"url":"https://datatracker.ietf.org/doc/html/rfc5849#section-3.4.3"}],"solutions":[{"lang":"en","value":"Upgrade to Net-OAuth 0.33 or later."}],"source":{"discovery":"UNKNOWN"},"title":"Net::OAuth versions before 0.33 for Perl allow the sender to choose the signature algorithm in verify","x_generator":{"engine":"cpansec-cna-tool 0.1"}}},"cveMetadata":{"assignerOrgId":"9b29abf9-4ab0-4765-b253-1875cd9b441e","assignerShortName":"CPANSec","cveId":"CVE-2026-72889","datePublished":"2026-08-19T07:20:09.095Z","dateReserved":"2026-08-10T15:44:58.172Z","dateUpdated":"2026-08-19T07:20:09.095Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-08-19 08:17:13","lastModifiedDate":"2026-08-19 08:17:13","problem_types":["CWE-347","CWE-757","CWE-347 CWE-347 Improper Verification of Cryptographic Signature","CWE-757 CWE-757 Selection of Less-Secure Algorithm During Negotiation ('Algorithm Downgrade')"],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"72889","Ordinal":"1","Title":"Net::OAuth versions before 0.33 for Perl allow the sender to cho","CVE":"CVE-2026-72889","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"72889","Ordinal":"1","NoteData":"Net::OAuth versions before 0.33 for Perl allow the sender to choose the signature algorithm in verify.\n\nverify resolves the signature method class from the signature_method parameter of the incoming message. signature_method is required on every request, so the algorithm used to check a signature is chosen by whoever sent it, and nothing lets the verifying party pin the method instead. When a message names HMAC-SHA1 or HMAC-SHA256, the key is derived from consumer_secret and token_secret rather than from the key the provider deployed.\n\nA provider deployed on RSA-SHA1 holds only the consumer public key, and RFC 5849 does not use consumer_secret for that method, so the required parameter is filled with a placeholder. A client that names HMAC-SHA1 instead has its signature checked against that placeholder, so a guessable one is enough to forge requests for any consumer key and token.","Type":"Description","Title":"Net::OAuth versions before 0.33 for Perl allow the sender to cho"}]}}}