CVE catalog

CVE-2018-20573

yaml-cpp: CVE-2018-20573

Severity: Medium · CVSS 5.3CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Published: Dec 28, 2018, 4:29:00 PM UTC
Source: [NVD] · [CVE record]
EPSS: 2.53% · Oct 25, 2026

The Scanner::EnsureTokensInQueue function in yaml-cpp (aka LibYaml-C++) 0.6.2 allows remote attackers to cause a denial of service (stack consumption and application crash) via a crafted YAML file.

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

Distribution	Package	Release	Version	Status
Debian	yaml-cpp	sid	`0.9.0+dfsg-10`	fixed
Debian	yaml-cpp	forky	`0.9.0+dfsg-9`	fixed
Debian	yaml-cpp	trixie	`0.8.0+dfsg-7`	fixed
Debian	yaml-cpp	bookworm	`0.7.0+dfsg-8`	fixed
Ubuntu	yaml-cpp	14.04	`0.3.0-1`	vulnerable
Ubuntu	yaml-cpp	14.04	`0.5.1-1`	vulnerable
Ubuntu	yaml-cpp	16.04	`0.5.2-2`	vulnerable
Ubuntu	yaml-cpp	16.04	`0.5.2-3`	vulnerable
Ubuntu	yaml-cpp	16.04	`0.5.2-4ubuntu1~16.04.4`	vulnerable
Ubuntu	yaml-cpp0.3	16.04	`0.3.0-1.2`	vulnerable
Ubuntu	yaml-cpp	18.04	`0.5.2-4ubuntu1`	vulnerable
Ubuntu	yaml-cpp0.3	18.04	`0.3.0-1.2`	vulnerable
Ubuntu	yaml-cpp	20.04	`0.6.2-4fakesync1`	vulnerable
Ubuntu	yaml-cpp	20.04	`0.6.2-4ubuntu1`	vulnerable
Suse	yaml-cpp	linux enterprise installer updates 15 sp2	`0.6.1-4.5.1`	fixed
Suse	yaml-cpp	linux enterprise module for basesystem 15 sp3	`0.6.1-4.5.1`	fixed
Suse	yaml-cpp	linux enterprise module for desktop applications 15 sp3	`0.6.1-4.5.1`	fixed
Suse	yaml-cpp	linux enterprise real time 15 sp2	`0.6.1-4.5.1`	fixed
Suse	yaml-cpp	linux enterprise micro 5.0	`0.6.1-4.5.1`	fixed
Suse	yaml-cpp	linux enterprise micro 5.1	`0.6.1-4.5.1`	fixed
Suse	yaml-cpp	linux enterprise workstation extension 12 sp5	`0.5.3-3.6.3`	fixed
Suse	yaml-cpp	linux enterprise micro 5.2	`0.6.1-4.5.1`	fixed
Opensuse	yaml-cpp	leap 15.3	`0.6.1-4.5.1`	fixed
Suse	yaml-cpp	linux enterprise high performance computing 15 sp2-ltss	`0.6.1-4.5.1`	fixed
Suse	yaml-cpp	linux enterprise server 15 sp2-ltss	`0.6.1-4.5.1`	fixed
Suse	yaml-cpp	linux enterprise server for sap applications 15 sp2	`0.6.1-4.5.1`	fixed
Suse	yaml-cpp	enterprise storage 7	`0.6.1-4.5.1`	fixed

Fixed-version evidence

Distribution	Package	Type	Release	Fixed version	Urgency	Origin	Bugs
Debian	yaml-cpp	source	sid	`0.6.3-1`	low	Not reported	[918147]
Debian	yaml-cpp	source	forky	`0.6.3-1`	low	Not reported	[918147]
Debian	yaml-cpp	source	trixie	`0.6.3-1`	low	Not reported	[918147]
Debian	yaml-cpp	source	bookworm	`0.6.3-1`	low	Not reported	[918147]
Suse	yaml-cpp	rpm	linux enterprise installer updates 15 sp2	`0.6.1-4.5.1`	Not reported	SUSE-SU-2022:1073-1	Not reported
Suse	yaml-cpp	rpm	linux enterprise module for basesystem 15 sp3	`0.6.1-4.5.1`	Not reported	SUSE-SU-2022:1073-1	Not reported
Suse	yaml-cpp	rpm	linux enterprise module for desktop applications 15 sp3	`0.6.1-4.5.1`	Not reported	SUSE-SU-2022:1073-1	Not reported
Suse	yaml-cpp	rpm	linux enterprise real time 15 sp2	`0.6.1-4.5.1`	Not reported	SUSE-SU-2022:1073-1	Not reported
Suse	yaml-cpp	rpm	linux enterprise micro 5.0	`0.6.1-4.5.1`	Not reported	SUSE-SU-2022:1073-1	Not reported
Suse	yaml-cpp	rpm	linux enterprise micro 5.1	`0.6.1-4.5.1`	Not reported	SUSE-SU-2022:1073-1	Not reported
Suse	yaml-cpp	rpm	linux enterprise workstation extension 12 sp5	`0.5.3-3.6.3`	Not reported	SUSE-SU-2022:1072-1	Not reported
Suse	yaml-cpp	rpm	linux enterprise micro 5.2	`0.6.1-4.5.1`	Not reported	SUSE-SU-2022:1073-2	Not reported
Opensuse	yaml-cpp	rpm	leap 15.3	`0.6.1-4.5.1`	Not reported	OPENSUSE-SU-2022:1073-1	Not reported
Suse	yaml-cpp	rpm	linux enterprise high performance computing 15 sp2-ltss	`0.6.1-4.5.1`	Not reported	SUSE-SU-2023:1740-3	Not reported
Suse	yaml-cpp	rpm	linux enterprise server 15 sp2-ltss	`0.6.1-4.5.1`	Not reported	SUSE-SU-2023:1740-3	Not reported
Suse	yaml-cpp	rpm	linux enterprise server for sap applications 15 sp2	`0.6.1-4.5.1`	Not reported	SUSE-SU-2023:1740-3	Not reported
Suse	yaml-cpp	rpm	enterprise storage 7	`0.6.1-4.5.1`	Not reported	SUSE-SU-2023:1740-3	Not reported

[Debian bug #918147]

OpenFactory catalog packages

[Debian 12 (Bookworm)]

[libyaml-cpp0.7]Fixed
Source package: [yaml-cpp]
Details (2)
- 0.7.0+dfsg-8+b1 · amd64 · bookworm
  Fixed · Fixed: 0.6.3-1
  dsa · yaml-cpp · debian · bookworm; dsa · yaml-cpp · debian · 12
- 0.7.0+dfsg-8+b1 · arm64 · bookworm
  Fixed · Fixed: 0.6.3-1
  dsa · yaml-cpp · debian · bookworm; dsa · yaml-cpp · debian · 12
[libyaml-cpp-dev]Fixed
Source package: [yaml-cpp]
Details (2)
- 0.7.0+dfsg-8+b1 · amd64 · bookworm
  Fixed · Fixed: 0.6.3-1
  dsa · yaml-cpp · debian · bookworm; dsa · yaml-cpp · debian · 12
- 0.7.0+dfsg-8+b1 · arm64 · bookworm
  Fixed · Fixed: 0.6.3-1
  dsa · yaml-cpp · debian · bookworm; dsa · yaml-cpp · debian · 12

[Debian 13 (Trixie)]

[libyaml-cpp0.8]Fixed
Source package: [yaml-cpp]
Details (2)
- 0.8.0+dfsg-7 · amd64 · trixie
  Fixed · Fixed: 0.6.3-1
  dsa · yaml-cpp · debian · 13
- 0.8.0+dfsg-7 · arm64 · trixie
  Fixed · Fixed: 0.6.3-1
  dsa · yaml-cpp · debian · 13
[libyaml-cpp-dev]Fixed
Source package: [yaml-cpp]
Details (2)
- 0.8.0+dfsg-7 · amd64 · trixie
  Fixed · Fixed: 0.6.3-1
  dsa · yaml-cpp · debian · 13
- 0.8.0+dfsg-7 · arm64 · trixie
  Fixed · Fixed: 0.6.3-1
  dsa · yaml-cpp · debian · 13

Observed: Oct 23, 2026, 5:36:04 PM UTC

References

[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [OSV Package Vulnerability Database] · [SUSE security advisories and VEX]