CVE-2026-5084
WebDyne::Session versions before 3.003_704 for Perl generate the session id insecurely
WebDyne::Session versions before 3.003_704 for Perl generate 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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
6.5
WebDyne::Session versions before 3.003_704 for Perl generate the session id insecurely
WebDyne::Session versions before 3.003_704 for Perl generate 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.
- Record
CVE-2026-5084- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-340, CWE-338
- Updated
- 2026-11-02
EUVDEUVD-2026-29039
6.5
WebDyne::Session versions before 3.003_704 for Perl generate 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.
- Record
EUVD-2026-29039- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-462c-h7qr-cxm6
6.5
WebDyne::Session versions through 2.075 for Perl generates the session id insecurely. The...
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.
- Record
GHSA-462c-h7qr-cxm6- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-338
- Updated
- 2026-11-02
NVD
6.5
WebDyne::Session versions before 3.003_704 for Perl generate 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.
- Record
CVE-2026-5084- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-338, CWE-340
- Updated
- 2026-11-02
OSV
6.5
WebDyne::Session versions before 3.003_704 for Perl generate the session id insecurely
WebDyne::Session versions before 3.003_704 for Perl generate 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.
- Record
CVE-2026-5084- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-338, CWE-340
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-5084 is a medium vulnerability (CVSS 6.5) in Aspeer Webdyne::session, published May 11, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.33%, the 26th percentile. No source names a fixed version.
References
metacpan.org/release/ASPEER/WebDyne-2.075/source/lib/WebDyne/Session.pm
github.com/aspeer/WebDyne/commit/7a3f949dc24e62a276eb0db629db64aca356e954.patch
webdyne.org
security.metacpan.org/docs/guides/random-data-for-security.html
openwall.com/lists/oss-security/2026/05/11/3
nvd.nist.gov/vuln/detail/CVE-2026-5084