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TI-2026-39348 Aliases CVE-2026-54502GHSA-3v45-f3vh-wg7m

Oj: Stack Buffer Overflow in Oj.dump via Large Indent

Priority HIGH 69CWE-121Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
None · None · Low
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub.

Summary

Oj (Optimized JSON) is a JSON parser and Object marshaller packaged as a Ruby gem. In versions prior to 3.17.2, Oj.dump is vulnerable to a stack-based buffer overflow when a large :indent value is provided by the developer. fill_indent in dump.h calls memset(indent_str, ' ', (size_t)opts->indent) without validating the size. When opts->indent is set to INT_MAX (2,147,483,647), the (size_t) cast preserves the large value and memset writes 2 GB into the stack-allocated out buffer (4,184 bytes), corrupting the stack and crashing the process. This issue has been fixed in version 3.17.2.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00401 34th percentileScored 2026-11-07
Fix Fixed oj (ohler55): 3.17.2oj (RubyGems): 3.17.3

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
ohler55ojbefore 3.17.23.17.2Patch availableCNA
—oj (RubyGems)before 3.17.33.17.3Patch availableGHSA-3v45-f3vh-wg7m
  • oj Vendorohler55 Affected before 3.17.2 Fixed in 3.17.2 Patch available CNA
  • oj (RubyGems) Vendor— Affected before 3.17.3 Fixed in 3.17.3 Patch available GHSA-3v45-f3vh-wg7m

Remediation

  • Fix · CNA oj (ohler55) Fixed in 3.17.2
  • Fix · GHSA-3v45-f3vh-wg7m oj (RubyGems) Fixed in 3.17.3 Advisory →

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-54502
  2. 2026-10-03 Alias added: GHSA-3v45-f3vh-wg7m

References

Other 2

  • TI-2026-39426 Oj: Stack Buffer Overflow in Oj::Doc#each_child via Deeply Nested Input CVSS 3.1HIGH 7.5
  • TI-2026-39672 Oj: Negative-Size memcpy in Oj::Parser create_id Attribute Handling CVSS 4.0MEDIUM 6.3
  • TI-2026-39675 Oj: Integer Overflow in Oj.load 2GB String Handling CVSS 4.0MEDIUM 6.3
  • TI-2026-39674 Oj: Use-After-Free in Oj::Parser SAJ Long Key Callback CVSS 4.0MEDIUM 6.3
  • TI-2026-39673 Oj: Use-After-Free in Oj::Parser array_class/hash_class GC Marking CVSS 4.0MEDIUM 6.3
  • TI-2026-39671 Oj: Use-After-Free in Oj::Parser Symbol Key Cache Toggle CVSS 4.0MEDIUM 6.3
See all 10 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences