CVEvulnerability
CVE-2026-4177
9.1 CRITICAL
Official page ↗
- Status
- Modified
- Published
- 2026-03-16
- Last modified
- 2026-07-15
- Assigner
- 9b29abf9-4ab0-4765-b253-1875cd9b441e
- CVSS 3.1 (134c704f-9b21-4f2e-91b3-4a467353bcc0)
- 9.1 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
- CVSS 3.1 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)
- 7.3 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
- Weaknesses
- CWE-120, CWE-122
Description
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.
Affected configurations
• toddr yaml\ \ (< 1.37)
Related
References
- https://github.com/cpan-authors/YAML-Syck/commit/e8844a31c8cf0052914b198fc784ed4e6b8ae69e.patch Patch
- https://metacpan.org/release/TODDR/YAML-Syck-1.37_01/changes#L21 Release Notes
- http://www.openwall.com/lists/oss-security/2026/03/16/6 Mailing List, Third Party Advisory
- https://access.redhat.com/errata/RHSA-2026:6470 access.redhat.com
- https://access.redhat.com/errata/RHSA-2026:8311 access.redhat.com
- https://access.redhat.com/security/cve/CVE-2026-4177 access.redhat.com
- https://bugzilla.redhat.com/show_bug.cgi?id=2448277 bugzilla.redhat.com
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4177.json security.access.redhat.com