GHSA-jj47-x69x-mxrm is a medium-severity (CVSS 5.9) CWE-122 vulnerability in yajl-ruby. 2 public exploit references exist, so weaponization risk is real. A fix is available for yajl-ruby — see the affected versions and patch details below.
Buffer Overflow in yajl-ruby
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for GHSA-jj47-x69x-mxrm.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-jj47-x69x-mxrm plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 379,145 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
yajl-rubyReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects RubyGems packages — download data is not available via public APIs for these ecosystems.
Description
NOTE: A previous patch, 1.4.2, fixed the heap memory issue, but could still lead to a DoS infinite loop. Please update to version 1.4.3
The 1.x branch and the 2.x branch of yajl contain an integer overflow which leads to subsequent heap memory corruption when dealing with large (~2GB) inputs.
Details
The reallocation logic at yajl_buf.c#L64 may result in the need 32bit integer wrapping to 0 when need approaches a value of 0x80000000 (i.e. ~2GB of data), which results in a reallocation of buf->alloc into a small heap chunk.
These integers are declared as size_t in the 2.x branch of yajl, which practically prevents the issue from triggering on 64bit platforms, however this does not preclude this issue triggering on 32bit builds on which size_t is a 32bit integer.
Subsequent population of this under-allocated heap chunk is based on the original buffer size, leading to heap memory corruption.
Impact
We rate this as a moderate severity vulnerability which mostly impacts process availability as we believe exploitation for arbitrary code execution to be unlikely.
Patches
Patched in yajl-ruby 1.4.3
Workarounds
Avoid passing large inputs to YAJL
References
For more information
If you have any questions or comments about this advisory:
- Open an issue in yajl-ruby
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💎RubyGems | yajl-ruby | all versions | 1.4.3bundle update yajl-ruby --conservative |
Research 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 yajl-ruby, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update yajl-ruby to 1.4.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-jj47-x69x-mxrm is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-jj47-x69x-mxrm can be triaged on real exposure rather than presence alone.
Tailored to GHSA-jj47-x69x-mxrm. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
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 Enterprise Linux only ships YAJL 2.x versions and on 32-bit systems, more than 2GiB of data will be required for triggering this bug. However, on 64-bit systems, more than 9EiB of data will be needed, making this vulnerability very hard to be exploited on these systems.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Enterprise Linux 8 | yajl-0:2.1.0-11.el8 | RHSA-2022:7524 |
| Red Hat Enterprise Linux 8.6 Extended Update Support | yajl-0:2.1.0-13.el8_6 | RHSA-2024:2063 |
| Red Hat Enterprise Linux 9 | yajl-0:2.1.0-21.el9 | RHSA-2022:8252 |
Frequently Asked Questions
Is GHSA-jj47-x69x-mxrm in your dependencies?
O3 Security finds GHSA-jj47-x69x-mxrm across RubyGems dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.