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DEBIAN-CVE-2026-13713

Type: advisorySource: OSV1 source record

YAML::Syck versions before 1.47 for Perl allow a use-after-free and double-free via an anchor node freed while still on the parser value stack. In the bundled libsyck, when an anchor name is redefined or removed, syck_hdlr_add_anchor and syck_hdlr_remove_anchor free the node stored under that name with syck_free_node. That node can still be live on the parser's value stack, so syck_hdlr_add_node reaches it again and frees it a second time. On a normal build the 48-byte node chunk is freed twice and the interpreter aborts. Anchors need no special flags, so this is reached on the default Load path, and a 7-byte document that redefines an anchor triggers it. Any caller that runs Load or LoadFile on an untrusted document that redefines an anchor mid-parse crashes the interpreter, a denial of service.

Announced Source revision 1
Original source ↗

DEBIAN-CVE-2026-13713

Primary source · Revision 1

Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.

Security context

Source reference: osv:DEBIAN-CVE-2026-13713

libyaml-syck-perl

Source reference: /affected/0/package/name

Affected versions
1.34-2

Source reference: /affected/0/versions

1.34-2+deb12u1

Source reference: /affected/0/versions

1.34-2+deb12u2

Source reference: /affected/0/versions

Fixed versions
1.34-2+deb12u3

Source reference: /affected/0/ranges

Prerequisites
Not stated in this record

libyaml-syck-perl

Source reference: /affected/1/package/name

Affected versions
1.34-2

Source reference: /affected/1/versions

1.34-2+deb13u1

Source reference: /affected/1/versions

1.34-2+deb13u2

Source reference: /affected/1/versions

Fixed versions
1.34-2+deb13u3

Source reference: /affected/1/ranges

Prerequisites
Not stated in this record

libyaml-syck-perl

Source reference: /affected/2/package/name

Affected versions
1.34-2

Source reference: /affected/2/versions

1.34-3

Source reference: /affected/2/versions

1.34-4

Source reference: /affected/2/versions

1.36-1

Source reference: /affected/2/versions

1.36-2

Source reference: /affected/2/versions

1.36-3

Source reference: /affected/2/versions

Fixed versions
1.47-1

Source reference: /affected/2/ranges

Prerequisites
Not stated in this record

Structured affected-version data

Original package identities and version rules from this source.

[
  {
    "ranges": [
      {
        "type": "ECOSYSTEM",
        "events": [
          {
            "introduced": "0"
          },
          {
            "fixed": "1.34-2+deb12u3"
          }
        ]
      }
    ],
    "package": {
      "name": "libyaml-syck-perl",
      "purl": "pkg:deb/debian/libyaml-syck-perl?arch=source&distro=bookworm",
      "ecosystem": "Debian:12"
    },
    "versions": [
      "1.34-2",
      "1.34-2+deb12u1",
      "1.34-2+deb12u2"
    ],
    "database_specific": {
      "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-13713.json"
    },
    "ecosystem_specific": {
      "urgency": "not yet assigned"
    }
  },
  {
    "ranges": [
      {
        "type": "ECOSYSTEM",
        "events": [
          {
            "introduced": "0"
          },
          {
            "fixed": "1.34-2+deb13u3"
          }
        ]
      }
    ],
    "package": {
      "name": "libyaml-syck-perl",
      "purl": "pkg:deb/debian/libyaml-syck-perl?arch=source&distro=trixie",
      "ecosystem": "Debian:13"
    },
    "versions": [
      "1.34-2",
      "1.34-2+deb13u1",
      "1.34-2+deb13u2"
    ],
    "database_specific": {
      "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-13713.json"
    },
    "ecosystem_specific": {
      "urgency": "not yet assigned"
    }
  },
  {
    "ranges": [
      {
        "type": "ECOSYSTEM",
        "events": [
          {
            "introduced": "0"
          },
          {
            "fixed": "1.47-1"
          }
        ]
      }
    ],
    "package": {
      "name": "libyaml-syck-perl",
      "purl": "pkg:deb/debian/libyaml-syck-perl?arch=source&distro=forky",
      "ecosystem": "Debian:14"
    },
    "versions": [
      "1.34-2",
      "1.34-3",
      "1.34-4",
      "1.36-1",
      "1.36-2",
      "1.36-3"
    ],
    "database_specific": {
      "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-13713.json"
    },
    "ecosystem_specific": {
      "urgency": "not yet assigned"
    }
  }
]

Publisher severity

No explicit severity was provided.

Event
#55512 · Revision 1
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Publisher date
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