Net::OAuth versions before 0.33 for Perl allow the sender to choose the signature algorithm in verify
Summary
| CVE | CVE-2026-72889 |
|---|---|
| State | PUBLISHED |
| Assigner | CPANSec |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-08-19 08:17:13 UTC |
| Updated | 2026-08-19 08:17:13 UTC |
| Description | Net::OAuth versions before 0.33 for Perl allow the sender to choose the signature algorithm in verify. verify 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. A 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. |
Risk And Classification
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')
There are no known software configurations currently associated with this CVE in NVD or the CVE Program record.
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/vurtdev/Net-OAuth/commit/c467adf45c8d77ac4b92ad78b3eebf949252... | 9b29abf9-4ab0-4765-b253-1875cd9b441e | github.com | |
| github.com/vurtdev/Net-OAuth/security/advisories/GHSA-c8rm-g5cm-4pf5 | 9b29abf9-4ab0-4765-b253-1875cd9b441e | github.com | |
| metacpan.org/release/RRWO/Net-OAuth-0.33/changes | 9b29abf9-4ab0-4765-b253-1875cd9b441e | metacpan.org | |
| datatracker.ietf.org/doc/html/rfc5849 | 9b29abf9-4ab0-4765-b253-1875cd9b441e | datatracker.ietf.org | |
| datatracker.ietf.org/doc/html/rfc5849 | 9b29abf9-4ab0-4765-b253-1875cd9b441e | datatracker.ietf.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
Additional Advisory Data
Solutions
CNA: Upgrade to Net-OAuth 0.33 or later.
There are currently no legacy QID mappings associated with this CVE.