Summaryinfo

A vulnerability described as problematic has been identified in KTAT HTTP::Session up to 0.53 on Perl. The impacted element is the function HTTP::Session::ID::SHA1 of the component Session ID Handler. Such manipulation leads to generation of predictable numbers or identifiers. This vulnerability is documented as CVE-2026-3256. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in KTAT HTTP::Session up to 0.53 on Perl. It has been rated as problematic. Affected by this issue is the function HTTP::Session::ID::SHA1 of the component Session ID Handler. 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 confidentiality. CVE summarizes:

HTTP::Session versions through 0.53 for Perl defaults to using insecurely generated session ids. HTTP::Session defaults to using HTTP::Session::ID::SHA1 to generate session ids using a SHA-1 hash seeded with the built-in rand function, the high resolution epoch time, and the PID. The PID will come from a small set of numbers, and the epoch time may be guessed, if it is not leaked from the HTTP Date header. The built-in rand function is unsuitable for cryptographic usage. The distribution includes HTTP::session::ID::MD5 which contains a similar flaw, but uses the MD5 hash instead.

The advisory is available at metacpan.org. This vulnerability is handled as CVE-2026-3256 since 02/26/2026. The exploitation is known to be difficult. The attack may be launched remotely. No form of authentication is required for exploitation. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1600.001 by the MITRE ATT&CK project.

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-2026-16939). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

• KTAT

Name

• HTTP::Session

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
• 0.18
• 0.19
• 0.20
• 0.21
• 0.22
• 0.23
• 0.24
• 0.25
• 0.26
• 0.27
• 0.28
• 0.29
• 0.30
• 0.31
• 0.32
• 0.33
• 0.34
• 0.35
• 0.36
• 0.37
• 0.38
• 0.39
• 0.40
• 0.41
• 0.42
• 0.43
• 0.44
• 0.45
• 0.46
• 0.47
• 0.48
• 0.49
• 0.50
• 0.51
• 0.52
• 0.53

CPE 2.3info

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CPE 2.2info

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