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.
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.
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)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.5 | 3.1 | HIGH |
|
3.9 | 3.6 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
| 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 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| leont | crypt::sysrandom::xs | < 0.010 | cpe:2.3:a:leont:crypt\:\:sysrandom\:\:xs:*:*:*:*:*:perl:*:* |
| URL | Tags |
|---|---|
| https://metacpan.org/dist/Crypt-SysRandom-XS/changes | Release Notes |
| https://metacpan.org/release/LEONT/Crypt-SysRandom-XS-0.011/source/lib/Crypt/SysRandom/XS.xs#L51-52 | Issue Tracking |