CVE-2019-25777

Description

YAML versions before 1.27_001 for Perl allow a loaded perl/glob document to replace any package variable, which can lead to arbitrary code execution. A perl/glob document names a package and a symbol, and supplies the value assigned to it. Nothing restricts the name, so the target can be @INC or YAML's own load options. A perl/glob document that sets $YAML::LoadCode or $YAML::UseCode turns on code loading, which is off by default, for every later Load() in the process. A perl/code document is then passed to a string eval, so an attacker who supplies two documents to separate Load() calls in one process can execute arbitrary Perl code.

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• What do statuses mean?
• Patch details

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Patch details

Severity score breakdown

CVSS version: CVSS v3.0

References

• MITRE
• NVD
• Launchpad
• Debian

Related Ubuntu Security Notices (USN)

• USN-8925-1
• YAML-LibYAML vulnerabilities
• 14 October 2026

Other references

• https://www.cve.org/CVERecord?id=CVE-2019-25777
• https://www.openwall.com/lists/oss-security/2026/10/05/7