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.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
None
No data modification
Availability
High
Complete denial of service
CVSS Vector v3.1
Weakness Type (CWE)
Vulnerable Products 1
| Configuration | From (including) | Up to (excluding) |
|---|---|---|
|
Toddr Yaml\
cpe:2.3:a:toddr:yaml\:\:syck:*:*:*:*:*:perl:*:*
|
— |
1.37
|
References 3
https://github.com/cpan-authors/YAML-Syck/commit/e8844a31c8cf0052914b198fc784ed…
9b29abf9-4ab0-4765-b253-1875cd9b441e
https://metacpan.org/release/TODDR/YAML-Syck-1.37_01/changes#L21
9b29abf9-4ab0-4765-b253-1875cd9b441e
http://www.openwall.com/lists/oss-security/2026/03/16/6
af854a3a-2127-422b-91ae-364da2661108