CVE-2026-33491

CVE-2026-33491 is a high-severity vulnerability in Zenc-lang Zen C with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-121.

Key facts

Description

Zen C is a systems programming language that compiles to human-readable GNU C/C11. Prior to version 0.4.4, a stack-based buffer overflow vulnerability in the Zen C compiler allows attackers to cause a compiler crash or potentially execute arbitrary code by providing a specially crafted Zen C source file (`.zc`) with excessively long struct, function, or trait identifiers. Users are advised to update to Zen C version v0.4.4 or later to receive a patch.

Frequently asked questions

What is CVE-2026-33491?
Zen C is a systems programming language that compiles to human-readable GNU C/C11. Prior to version 0.4.4, a stack-based buffer overflow vulnerability in the Zen C compiler allows attackers to cause a compiler crash or potentially execute arbitrary code by providing a specially crafted Zen C source file (`.zc`) with excessively long struct, function, or trait identifiers. Users are advised to update to Zen C version v0.4.4 or later to receive a patch.
How severe is CVE-2026-33491?
CVE-2026-33491 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-33491 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-33491?
CVE-2026-33491 affects Zenc-lang Zen C. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-33491?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-33491 have an EU (EUVD) identifier?
Yes. CVE-2026-33491 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-16319.
When was CVE-2026-33491 published?
CVE-2026-33491 was published on 2026-03-26 and last updated on 2026-06-17.

References

Affected products (1)

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