CVE-2026-54502Public exploitNetwork attack vector

Process crash via unchecked dump indentation

Published Jun 30, 2026 · Updated Jun 30, 2026

Stack-based buffer overflow in Oj before 3.17.2 allows remote attackers to crash a Ruby process through a large dump indent value. fill_indent multiplies an unchecked integer indent by nesting depth and passes the resulting length to memset against the 4,184-byte stack-allocated out buffer. Exploitation requires an application path that forwards an attacker-controlled indent option to Oj.dump; the demonstrated consequence is process termination from stack corruption.

CVSS severity6.3
Medium
EPSS probability0.34%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack-based buffer overflow in Oj before 3.17.2 allows remote attackers to crash a Ruby process through a large dump indent value. fill_indent multiplies an unchecked integer indent by nesting depth and passes the resulting length to memset against the 4,184-byte stack-allocated out buffer. Exploitation requires an application path that forwards an attacker-controlled indent option to Oj.dump; the demonstrated consequence is process termination from stack corruption.

The record

CVE
CVE-2026-54502
Published
Jun 30, 2026
Updated
Jun 30, 2026
Vendor
Peter Ohler
Product
Oj
Classifications
CWE-121, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 30, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 30, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 3.17.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Peter Ohler · Ojversion=< 3.17.2

Published CVSS scores

6.3GitHub, Inc.CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-121Stack-based Buffer Overflow
T1499.004Endpoint Denial of Service: Application or System Exploitation

Public exploit references

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Technologies

Your stack

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Your stack

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