HAYAJO Mojolicious::Plugin::Web::Auth::OAuth2 up to 0.17 on Perl rand generation of predictable numbers or identifiers

Summaryinfo

A vulnerability classified as problematic has been found in HAYAJO Mojolicious::Plugin::Web::Auth::OAuth2 up to 0.17 on Perl. This affects the function rand. The manipulation leads to generation of predictable numbers or identifiers. This vulnerability is referenced as CVE-2026-9733. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability was found in HAYAJO Mojolicious::Plugin::Web::Auth::OAuth2 up to 0.17 on Perl and classified as problematic. This issue affects the function rand. The manipulation with an unknown input leads to a generation of predictable numbers or identifiers vulnerability. Using CWE to declare the problem leads to CWE-340. The product uses a scheme that generates numbers or identifiers that are more predictable than required. Impacted is integrity. The summary by CVE is:

Mojolicious::Plugin::Web::Auth::OAuth2 versions through 0.17 for Perl have an insecure default state parameter. When no state generator is specified in the constructor, the module defaults to using a SHA-1 hash of predictable and low-entropy sources, including the epoch time (which is leaked via the HTTP Date header) and a call to Perl's built-in rand function. A predictable state allows an attacker to hijack another user's session through cross site request forgery (CSRF).

It is possible to read the advisory at metacpan.org. The identification of this vulnerability is CVE-2026-9733 since 05/27/2026. The exploitation is known to be difficult. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 06/23/2026). The attack technique deployed by this issue is T1600.001 according to MITRE ATT&CK.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-38421). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

• HAYAJO

Name

• Mojolicious::Plugin::Web::Auth::OAuth2

Version

• 0.1
• 0.2
• 0.3
• 0.4
• 0.5
• 0.6
• 0.7
• 0.8
• 0.9
• 0.10
• 0.11
• 0.12
• 0.13
• 0.14
• 0.15
• 0.16
• 0.17

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Discussion