CVE-2026-54502: Stack-based Buffer Overflow in ohler55 oj
Affects ojSource GCVE Database
Not known to be exploited : upgrade to 3.17.2 when convenient.
Data as of 26 Oct 2026, 12:29 UTC
Rated by Threat Radar · No CVSS score from NVD or the CNA
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 26% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Affects
- versions prior to 3.17.2
- Patch
- Available – fixed in 3.17.2
Exploitation evidence
Disclosed: evidence found.
CVE published 1 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade oj to 3.17.2.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
RubyGemsojpkg:gem/ojOther threats | Affected
| Fixed in
|
Ubuntu 14.04 LTSruby-ojpkg:deb/ubuntu/ruby-oj?arch=source&distro=trustyOther threats | Affected
| Fixed in– |
Ubuntu 16.04 LTSruby-ojpkg:deb/ubuntu/ruby-oj?arch=source&distro=xenialOther threats | Affected
| Fixed in– |
Ubuntu 18.04 LTSruby-ojpkg:deb/ubuntu/ruby-oj?arch=source&distro=bionicOther threats | Affected
| Fixed in– |
Ubuntu 20.04 LTSruby-ojpkg:deb/ubuntu/ruby-oj?arch=source&distro=focalOther threats | Affected
| Fixed in– |
Ubuntu 22.04 LTSruby-ojpkg:deb/ubuntu/ruby-oj?arch=source&distro=jammyOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade Oj to version 3.17.2 or later, where this vulnerability has been fixed. No other mitigations are indicated by the vendor advisory.
Description
CVE-2026-54502 is a stack-based buffer overflow vulnerability in the Oj Ruby gem used for JSON parsing and marshalling. The flaw exists in versions prior to 3.17.2 in the Oj.dump function when a very large :indent value is specified. This causes the fill_indent function to call memset with an unchecked size, leading to a stack overflow. The issue has been fixed in version 3.17.2.