CVE-2026-16634: CWE-1104 Use of Unmaintained Third Party Components in FELIPE TOML::XS
TOML::XS versions before 0.06 for Perl bundle an unsupported and vulnerable version of tomlc99. The tomlc99 library is no longer maintained, and has an uncontrolled recursion vulnerability publicly reported in the issue tracker. Any caller that passes untrusted TOML to from_toml risks a stack overflow from a deeply-nested document. TOML::XS version 0.06 or later uses the successor tomlc17 library.
AI Analysis
Technical Summary
CVE-2026-16634 affects TOML::XS versions before 0.06, which bundle the unmaintained tomlc99 library. Tomlc99 contains an uncontrolled recursion vulnerability that can cause a stack overflow if untrusted TOML input with deeply nested structures is passed to the from_toml function. This vulnerability arises from the use of an unmaintained third-party component (CWE-1104) and results in a critical severity issue with a CVSS score of 9.8. The vulnerability is addressed in TOML::XS version 0.06 and later by replacing tomlc99 with the successor library tomlc17.
Potential Impact
An attacker can cause a stack overflow by supplying deeply nested TOML documents to the from_toml function in vulnerable versions of TOML::XS. This can lead to denial of service and potentially arbitrary code execution due to the uncontrolled recursion in the unmaintained tomlc99 library. The vulnerability affects confidentiality, integrity, and availability as indicated by the CVSS vector.
Mitigation Recommendations
Upgrade to TOML::XS version 0.06 or later, which replaces the vulnerable tomlc99 library with the maintained tomlc17 library. No other remediation or temporary fixes are documented. Patch status is not explicitly confirmed in the advisory, but the upgrade to version 0.06 or later is the effective fix.
CVE-2026-16634: CWE-1104 Use of Unmaintained Third Party Components in FELIPE TOML::XS
Description
TOML::XS versions before 0.06 for Perl bundle an unsupported and vulnerable version of tomlc99. The tomlc99 library is no longer maintained, and has an uncontrolled recursion vulnerability publicly reported in the issue tracker. Any caller that passes untrusted TOML to from_toml risks a stack overflow from a deeply-nested document. TOML::XS version 0.06 or later uses the successor tomlc17 library.
CVSS v3.1
Score 9.8critical
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-16634 affects TOML::XS versions before 0.06, which bundle the unmaintained tomlc99 library. Tomlc99 contains an uncontrolled recursion vulnerability that can cause a stack overflow if untrusted TOML input with deeply nested structures is passed to the from_toml function. This vulnerability arises from the use of an unmaintained third-party component (CWE-1104) and results in a critical severity issue with a CVSS score of 9.8. The vulnerability is addressed in TOML::XS version 0.06 and later by replacing tomlc99 with the successor library tomlc17.
Potential Impact
An attacker can cause a stack overflow by supplying deeply nested TOML documents to the from_toml function in vulnerable versions of TOML::XS. This can lead to denial of service and potentially arbitrary code execution due to the uncontrolled recursion in the unmaintained tomlc99 library. The vulnerability affects confidentiality, integrity, and availability as indicated by the CVSS vector.
Mitigation Recommendations
Upgrade to TOML::XS version 0.06 or later, which replaces the vulnerable tomlc99 library with the maintained tomlc17 library. No other remediation or temporary fixes are documented. Patch status is not explicitly confirmed in the advisory, but the upgrade to version 0.06 or later is the effective fix.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- CPANSec
- Date Reserved
- 2026-07-22T16:37:55.533Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a63396e9c2644c7f8bb3cba
Added to database: 07/24/2026, 10:07:42 UTC
Last enriched: 07/31/2026, 14:55:02 UTC
Last updated: 09/07/2026, 11:09:30 UTC
Views: 93
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