snakeYAML before 1.31 vulnerable to Denial of Service due to Out-of-bounds WriteGHSA-hhhw-99gj-p3c3
MEDIUMGHSA-hhhw-99gj-p3c3 is a medium-severity (CVSS 5.5) CWE-121 vulnerability in org.yaml:snakeyaml. 2 public exploit or proof-of-concept references are indexed, so weaponization risk is real. A fix is available for org.yaml:snakeyaml — see the affected versions and patch details below.
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-hhhw-99gj-p3c3.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
org.yaml:snakeyamlReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
Using snakeYAML to parse untrusted YAML files may be vulnerable to Denial of Service attacks (DOS). If the parser is running on user supplied input, an attacker may supply content that causes the parser to crash by stackoverflow.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.yaml:snakeyaml | all versions | 1.31org.yaml:snakeyaml:1.31 |
Affected Products
debian linuxdebiansnakeyamlsnakeyaml_projectResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.yaml:snakeyaml, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.yaml:snakeyaml to 1.31 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-hhhw-99gj-p3c3 is resolved across your whole dependency graph.
Workarounds
Stop feeding it untrusted input: reject or quarantine files and payloads from unverified sources until you can upgrade, restrict accepted formats to the ones you actually need, and run the parsing or decoding step in a least-privileged sandbox or short-lived worker so a crash or corrupted read cannot reach the rest of the process.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
Red Hat Build of Quarkus is not affected by this issue as it already includes the fixed version. Satellite component Candlepin does not directly use snakeyaml, so it is not affected. Regardless, an update with the latest, unaffected snakeyaml version will be provided at next release.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat AMQ Broker 7 | snakeyaml | RHSA-2022:8876 |
| Red Hat build of Eclipse Vert.x 4.3.3 | snakeyaml | RHSA-2022:6757 |
| Red Hat Data Grid 8.4.0 | snakeyaml | RHSA-2022:8524 |
| Red Hat Satellite 6.13 for RHEL 8 | candlepin-0:4.2.13-1.el8sat | RHSA-2023:2097 |
| Red Hat Single Sign-On 7 | snakeyaml | RHSA-2023:1049 |
| Red Hat Single Sign-On 7.6 for RHEL 7 | rh-sso7-keycloak-0:18.0.6-1.redhat_00001.1.el7sso | RHSA-2023:1043 |
| Red Hat Single Sign-On 7.6 for RHEL 8 | rh-sso7-keycloak-0:18.0.6-1.redhat_00001.1.el8sso | RHSA-2023:1044 |
| Red Hat Single Sign-On 7.6 for RHEL 9 | rh-sso7-keycloak-0:18.0.6-1.redhat_00001.1.el9sso | RHSA-2023:1045 |
Frequently Asked Questions
Is GHSA-hhhw-99gj-p3c3 in your dependencies?
Find it across Maven, including transitive dependencies.