CVE-2026-4177 (GCVE-0-2026-4177)
Vulnerability from cvelistv5
Published
2026-03-16 22:30
Modified
2026-07-15 00:58
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-122 - Heap-based Buffer Overflow
Summary
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.
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| TODDR | YAML::Syck |
Version: 0 < |
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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