CPANSA-WebDyne-2026-5084: WebDyne vulnerability
| Publisher | giterlizzi | Document category | csaf_security_advisory |
|---|---|---|---|
| Initial release date | 2026-05-11T00:00:00 | Engine | CSAF Perl Toolkit 0.26 |
| Current release date | 2026-05-11T00:00:00 | Build Date | |
| Current version | 1 | Status | final |
| CVSS v3.1 Base Score | 6.5 | Severity | |
| Original language | Language | en | |
| Also referred to | |||
Vulnerability Description
WebDyne::Session versions through 2.075 for Perl generates the session id insecurely. The session handler generates the session id from an MD5 hash seeded with a call to the built-in rand() function. The rand function is passed a maximum value based on the process id, the epoch time and the reference address of the object, but this information will have no effect on the overall quality of the seed of the message digest. The rand function is seeded by 32-bits and is predictable. It is considered unsuitable for cryptographic purposes. Predictable session ids could allow an attacker to gain access to systems. Note that WebDyne::Session versions 1.042 and earlier appear to be in separate distributions from WebDyne.
Vulnerabilities
CVE-2026-5084
Vulnerability DescriptionWebDyne::Session versions through 2.075 for Perl generates the session id insecurely.
The session handler generates the session id from an MD5 hash seeded with a call to the built-in rand() function. The rand function is passed a maximum value based on the process id, the epoch time and the reference address of the object, but this information will have no effect on the overall quality of the seed of the message digest.
The rand function is seeded by 32-bits and is predictable. It is considered unsuitable for cryptographic purposes.
Predictable session ids could allow an attacker to gain access to systems.
Note that WebDyne::Session versions 1.042 and earlier appear to be in separate distributions from WebDyne.
| Weakness | CWE-338 : Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) |
|---|
Product status
Known affected
| Product | Score | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| WebDyne greater than 0 |
|
giterlizzi
Namespace: https://github.com/giterlizzi/
gdt@cpan.org
References
- CPANSA-WebDyne-2026-5084 JSON self
https://raw.githubusercontent.com/giterlizzi/perl-CPANSA-CSAF/develop/csaf/white/2026/cpansa-webdyne-2026-5084.json - https://metacpan.org/release/ASPEER/WebDyne-2.075/source/lib/WebDyne/Session.pm#L120 external
https://metacpan.org/release/ASPEER/WebDyne-2.075/source/lib/WebDyne/Session.pm#L120 - https://security.metacpan.org/docs/guides/random-data-for-security.html external
https://security.metacpan.org/docs/guides/random-data-for-security.html - https://webdyne.org external
https://webdyne.org - http://www.openwall.com/lists/oss-security/2026/05/11/3 external
http://www.openwall.com/lists/oss-security/2026/05/11/3 - CVE-2026-5084 (NVD) external
https://nvd.nist.gov/vuln/detail/CVE-2026-5084
Revision history
| Version | Date of the revision | Summary of the revision |
|---|---|---|
| 1 | Mon May 11 00:00:00 2026 | First release |
Sharing rules
TLP:WHITE
For the TLP version see: https://www.first.org/tlp/