CPANSA-Crypt-SysRandom-XS-2026-2597: Crypt-SysRandom-XS vulnerability

Publisher giterlizzi Document category csaf_security_advisory
Initial release date 2026-02-27T00:00:00 Engine CSAF Perl Toolkit 0.26
Current release date 2026-02-27T00:00:00 Build Date
Current version 1 Status final
CVSS v3.1 Base Score 7.5 Severity
Original language Language en
Also referred to

Vulnerability Description

Crypt::SysRandom::XS versions before 0.010 for Perl is vulnerable to a heap buffer overflow in the XS function random_bytes(). The function does not validate that the length parameter is non-negative. If a negative value (e.g. -1) is supplied, the expression length + 1u causes an integer wraparound, resulting in a zero-byte allocation. The subsequent call to chosen random function (e.g. getrandom) passes the original negative value, which is implicitly converted to a large unsigned value (typically SIZE_MAX). This can result in writes beyond the allocated buffer, leading to heap memory corruption and application crash (denial of service). In common usage, the length argument is typically hardcoded by the caller, which reduces the likelihood of attacker-controlled exploitation. Applications that pass untrusted input to this parameter may be affected.

Vulnerabilities

CVE-2026-2597

Vulnerability Description

Crypt::SysRandom::XS versions before 0.010 for Perl is vulnerable to a heap buffer overflow in the XS function random_bytes().

The function does not validate that the length parameter is non-negative. If a negative value (e.g. -1) is supplied, the expression length + 1u causes an integer wraparound, resulting in a zero-byte allocation. The subsequent call to chosen random function (e.g. getrandom) passes the original negative value, which is implicitly converted to a large unsigned value (typically SIZE_MAX). This can result in writes beyond the allocated buffer, leading to heap memory corruption and application crash (denial of service).

In common usage, the length argument is typically hardcoded by the caller, which reduces the likelihood of attacker-controlled exploitation. Applications that pass untrusted input to this parameter may be affected.

Weakness CWE-122 : Heap-based Buffer Overflow

Product status

Known affected
Product Score
Crypt-SysRandom-XS less than 0.010
CVSS Version CVSS Vector CVSS Base Score CVSS Base Severity
3.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H 7.5 High
Fixed

giterlizzi

Namespace: https://github.com/giterlizzi/

gdt@cpan.org

References

Revision history

Version Date of the revision Summary of the revision
1 Fri Feb 27 00:00:00 2026 First release

Sharing rules

TLP:WHITE
For the TLP version see: https://www.first.org/tlp/