UBUNTU-CVE-2019-25777

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.

References

Affected packages

Ubuntu:Pro:16.04:LTS / libyaml-perl

Package

Name: libyaml-perl
Purl: pkg:deb/ubuntu/libyaml-perl?arch=source&distro=esm-infra-legacy%2Fxenial

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0 Unknown introduced version / All previous versions are affected

Fixed

1.15-1ubuntu0.1~esm1

Affected versions

1.*

1.13-1

1.15-1

Ecosystem specific

{
    "availability":  "Available with Ubuntu Pro with Legacy support add-on: https://ubuntu.com/pro",
    "binaries":  [
        {
            "binary_name":  "libyaml-perl",
            "binary_version":  "1.15-1ubuntu0.1~esm1"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2019/UBUNTU-CVE-2019-25777.json"

Ubuntu:Pro:18.04:LTS / libyaml-perl