CVE-2026-72889
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. 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.
INFO
Published Date :
Aug. 19, 2026, 8:17 a.m.
Last Modified :
Aug. 19, 2026, 8:17 a.m.
Remotely Exploit :
No
Source :
9b29abf9-4ab0-4765-b253-1875cd9b441e
Affected Products
The following products are affected by CVE-2026-72889
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
Solution
- Update Net::OAuth to version 0.33 or later.
- Ensure signature methods are validated correctly.
- Verify secrets are used with appropriate algorithms.
- Implement strict checks on incoming signatures.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-72889.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-72889 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-72889
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-72889 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-72889 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by 9b29abf9-4ab0-4765-b253-1875cd9b441e
Aug. 19, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://github.com/vurtdev/Net-OAuth', 'modules': ['Net::OAuth'], 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '0.33', 'versionType': 'custom'}], 'packageURL': 'pkg:cpan/Net-OAuth', 'packageName': 'Net-OAuth', 'programFiles': ['lib/Net/OAuth/Message.pm', 'lib/Net/OAuth/Request.pm'], 'collectionURL': 'https://cpan.org/modules', 'defaultStatus': 'unaffected', 'programRoutines': [{'name': 'Net::OAuth::Message::verify'}, {'name': 'Net::OAuth::Message::_signature_method_class'}, {'name': 'Net::OAuth::Request::signature_key'}]}] Added 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. Added CWE CWE-347 Added CWE CWE-757 Added Reference https://datatracker.ietf.org/doc/html/rfc5849#section-3.4.2 Added Reference https://datatracker.ietf.org/doc/html/rfc5849#section-3.4.3 Added Reference https://github.com/vurtdev/Net-OAuth/commit/c467adf45c8d77ac4b92ad78b3eebf949252ba7f.patch Added Reference https://github.com/vurtdev/Net-OAuth/security/advisories/GHSA-c8rm-g5cm-4pf5 Added Reference https://metacpan.org/release/RRWO/Net-OAuth-0.33/changes