CVE-2026-4177YAML::Syck versions through 1.36 for Perl has several potential security vulnerabilities including a high-severity heap buffer overflow in the YAML emitter.
Updated under an hour ago ()
Does this affect you?
It affects toddr yaml::syck. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
Do this next
Free account, 1 product
YAML::Syck versions through 1.36 for Perl has several potential security vulnerabilities including a high-severity heap buffer overflow in the YAML emitter. The heap overflow occurs when class names exceed the initial 512-byte allocation. The base64 decoder could read past the buffer end on trailing newlines. strtok mutated n->type_id in place, corrupting shared node data. A memory leak occurred in syck_hdlr_add_anchor when a node already had an anchor. The incoming anchor string 'a' was leaked on early return.
- CVSS
- 9.1 CRITICAL (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
- Weakness (CWE)
- CWE-122, CWE-120
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- Not given
- NVD analysis
- Modified
- Record last updated
- Jul 15, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
toddr yaml::syck toddr:yaml::syck | before 1.37 | NVD |
References
- https://github.com/cpan-authors/YAML-Syck/commit/e8844a31c8cf0052914b198fc784ed4e6b8ae69e.patchpatch
- https://metacpan.org/release/TODDR/YAML-Syck-1.37_01/changes#L21release-notes
- http://www.openwall.com/lists/oss-security/2026/03/16/6mailing-list, third-party-advisory
- https://access.redhat.com/errata/RHSA-2026:6470
- https://access.redhat.com/errata/RHSA-2026:8311
- https://access.redhat.com/security/cve/CVE-2026-4177
- https://bugzilla.redhat.com/show_bug.cgi?id=2448277
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4177.json
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.