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TI-2026-25887 Aliases CVE-2026-33491

Zen-C has Stack-Based Buffer Overflow in Identifier Mangling

Priority HIGH 69CWE-121Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-121 and the CVSS impact.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00243 15th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed zenc (zenc-lang): 0.4.4

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
zenc-langzencbefore 0.4.40.4.4Patch availableCNA
  • zenc Vendorzenc-lang Affected before 0.4.4 Fixed in 0.4.4 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:zenc-lang:zen_c:*:*:*:*:*:*:*:*before 0.4.4Vulnerablezenc-lang
  • cpe:2.3:a:zenc-lang:zen_c:*:*:*:*:*:*:*:* Versions before 0.4.4 Vulnerable ·zenc-lang

Remediation

  • Fix · CNA zenc (zenc-lang) Fixed in 0.4.4

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-33491

References

Exploit 1

  • TI-2026-22542 Zen-C Vulnerable to Command Injection via Malicious Output Filename CVSS 3.1HIGH 7.3

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences