CVE-2026-54898
Oj (Optimized JSON) is a JSON parser and Object marshaller packaged as a Ruby gem. In versions prior to 3.17.2,Oj::Parser#parse is vulnerable to a heap use-after-free when a SAJ/SAJ2 callback mutates the input JSON string during parsing. The C engine holds a raw const byte * pointer into the Ruby string's internal buffer. If a callback (e.g. hash_start) resizes the string — for example by calling String#replace with a longer value — Ruby reallocates the string buffer and frees the old one. The C parser's pointer is left dangling; the next character read at parser.c:607 is a use-after-free. This issue has been fixed in version 3.17.2.
CVSS
- Version: 4.0
- Vector: CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- Base score: 2.1
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.15%
- Percentile among all scored CVEs: 3
- Score date: 10/2/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (1)
⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.
CWEs
- CWE-416
References
Raw JSON (NVD)
Show
{
"id": "CVE-2026-54898",
"cveTags": [],
"metrics": {
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"timestamp": "2026-07-01T13:36:39.350965Z"
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"vulnerabilityResponseEffort": "NOT_DEFINED",
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"affected": [
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"affectedData": [
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"published": "2026-07-01T00:16:33.103",
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"vulnStatus": "Deferred",
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"description": [
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"descriptions": [
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"value": "Oj (Optimized JSON) is a JSON parser and Object marshaller packaged as a Ruby gem. In versions prior to 3.17.2,Oj::Parser#parse is vulnerable to a heap use-after-free when a SAJ/SAJ2 callback mutates the input JSON string during parsing. The C engine holds a raw const byte * pointer into the Ruby string's internal buffer. If a callback (e.g. hash_start) resizes the string — for example by calling String#replace with a longer value — Ruby reallocates the string buffer and frees the old one. The C parser's pointer is left dangling; the next character read at parser.c:607 is a use-after-free. This issue has been fixed in version 3.17.2."
}
],
"lastModified": "2026-07-01T15:27:14.107",
"sourceIdentifier": "security-advisories@github.com"
}