CVE-2026-16634
TOML::XS versions before 0.06 for Perl bundle an unsupported and vulnerable version of tomlc99
- 9.8CriticalCVSS base score
- 0.82%Exploitation in 30 daysEPSS · top 42% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- YesPublic exploitsa reference or SSVC says so
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 The tomlc99 library is no longer maintained, and has an uncontrolled recursion vulnerability publicly reported in the issue tracker.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.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. A reference of the record is tagged as an exploit.
Show the exploits1
References tagged exploit1 reference
- https://github.com/cktan/tomlc99/issues/97 (opens in a new tab)issue-trackingexploit
Timeline
ID reserved
By CPANSec
- 2 days later
· 2 days later
Published
- 3 days later
· 3 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADPADP (enrichment) | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Deferred | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.82% · top 42% of all CVEs (11 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Affected products
What to do
Solution: Upgrade to TOML::XS version 0.06 or later.
Workaround: Only parse trusted TOML files.
References
References6
- https://metacpan.org/release/FELIPE/TOML-XS-0.06/changes (opens in a new tab)release-notes
- https://raw.githubusercontent.com/cktan/tomlc99/29076dfd095bbbbd50a3c1b2760d29f4b83e74ac/README.md (opens in a new tab)
- https://github.com/cktan/tomlc99/issues/97 (opens in a new tab)issue-trackingexploit
- https://github.com/cktan/tomlc17 (opens in a new tab)
- https://toml.io/en/v1.0.0 (opens in a new tab)technical-description
- http://www.openwall.com/lists/oss-security/2026/07/24/4 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-48547 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-16634)Record last updated .