ohler55 oj up to 3.17.1 parser.c Oj::Parser#parse use after free

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k0.00

Summaryinfo

A vulnerability was found in ohler55 oj up to 3.17.1 and classified as critical. This issue affects the function Oj::Parser#parse of the file parser.c. The manipulation results in use after free. This vulnerability is cataloged as CVE-2026-54898. The attack must be initiated from a local position. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in ohler55 oj up to 3.17.1. Affected is the function Oj::Parser#parse of the file parser.c. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability is traded as CVE-2026-54898 since 06/16/2026. The exploitability is told to be easy. Local access is required to approach this attack. Technical details are known, but there is no available exploit.

Upgrading to version 3.17.2 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: oj 3.17.2

Timelineinfo

06/16/2026 CVE reserved
07/01/2026 +15 days Advisory disclosed
07/01/2026 +0 days VulDB entry created
07/01/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-q2gm-54r6-8fwm
Status: Confirmed

CVE: CVE-2026-54898 (🔒)
GCVE (CVE): GCVE-0-2026-54898
GCVE (VulDB): GCVE-100-374994

Entryinfo

Created: 07/01/2026 07:13
Changes: 07/01/2026 07:13 (69)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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