CVE-2026-2597 | Crypt::SysRandom::XS versions before 0.010 for Perl is vulnerable to a heap buffer overflow in the XS function random_bytes()

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.

Published: 2026-02-27 Last update: 2026-03-03 Assigner: 9b29abf9-4ab0-4765-b253-1875cd9b441e Source: 9b29abf9-4ab0-4765-b253-1875cd9b441e

Conclusion & alert: CVE-2026-2597 is rated Low Risk (37.6/100): CVSS High severity, with low exploitation likelihood (EPSS 0.29%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-2597

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.05% 0.29% +0.24%
2 2026-03-30 0.05% 0.05% +0.00%
3 2026-03-05 0.05%

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-2597

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 3.6 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2026-2597

OS Trackers for CVE-2026-2597

vendor priority summary link
debian not yet assigned CVE-2026-2597 not yet assigned priority: Debian including 1 source packages (libcrypt-sysrandom-xs-perl), 2 status rows across 2 suites (forky, sid): resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-2597
ubuntu medium CVE-2026-2597 medium priority: Ubuntu including 1 source packages (libcrypt-sysrandom-xs-perl), 4 status rows across 4 suites (jammy, noble, questing, upstream): DNE 2, needs-triage 1, released 1. https://ubuntu.com/security/CVE-2026-2597

Affected software / configurations for CVE-2026-2597

Vendor Product Version Raw CPE
leont crypt::sysrandom::xs < 0.010 cpe:2.3:a:leont:crypt\:\:sysrandom\:\:xs:*:*:*:*:*:perl:*:*

References for CVE-2026-2597

cvelogic Threat Intelligence