YAML up to 1.27_000 glob Load code injection

Summaryinfo

A vulnerability, which was classified as critical, has been found in YAML up to 1.27_000. The impacted element is the function Load of the component glob. The manipulation leads to code injection. This vulnerability is traded as CVE-2019-25777. It is possible to initiate the attack remotely. There is no exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in YAML up to 1.27_000 and classified as critical. This issue affects the function Load of the component glob. The manipulation with an unknown input leads to a code injection vulnerability. Using CWE to declare the problem leads to CWE-94. The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2019-25777 since 09/21/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1059 according to MITRE ATT&CK.

Upgrading to version 1.27_001 eliminates this vulnerability.

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Productinfo

Name

• YAML

Version

• 1

CPE 2.3info

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CPE 2.2info

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