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TI-2026-62968 Aliases CVE-2026-93395GHSA-jm9m-v7jc-m4j8

Integer Underflow → Heap Out-of-Bounds Read in `bson_new_from_buffer()

Priority LOW 37CWE-191Published · Updated

Key facts

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

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

Summary

A missing lower-bound validation in the bson_new_from_buffer() function of libbson allows an integer underflow when processing BSON data with a zero-length prefix. The function reads a 32-bit document length from the input buffer but does not verify that the value is at least 5 (the minimum valid BSON document size) before using it in an array index calculation. When the length field is zero, the expression used to check the document's null terminator wraps to UINT32_MAX, causing a heap out-of-bounds read that crashes the process. An unauthorized party who can supply crafted BSON input to an application using this API can cause a denial of service.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00402 34th percentileScored 2026-11-07
Fix Fixed C Driver (MongoDB Inc.): 2.3.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

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

Affected products

VendorProductAffected versionsFixed inStatusSource
MongoDBC Driver2.0.0 to before 2.3.12.3.1Patch availableCNA
  • C Driver VendorMongoDB Affected 2.0.0 to before 2.3.1 Fixed in 2.3.1 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:mongodb:c_driver:*:*:*:*:*:mongodb:*:*2.0.0 to before 2.3.1VulnerableMongoDB
  • cpe:2.3:a:mongodb:c_driver:*:*:*:*:*:mongodb:*:* Versions 2.0.0 to before 2.3.1 Vulnerable ·MongoDB

Remediation

  • Fix · CNA C Driver (MongoDB Inc.) Fixed in 2.3.1

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-93395
  2. 2026-10-03 Alias added: GHSA-jm9m-v7jc-m4j8

References

Other 1

  • TI-2026-62966 Heap overflow via oversized decrypted TLS record sequence in Windows Secure Channel stream CVSS 4.0CRITICAL 9.2
  • TI-2026-05870 MongoDB C Driver Cyrus SASL Canonicalization Buffer Overflow CVSS 4.0HIGH 8.6
  • TI-2024-07001 Accessing Untrusted Directory May Allow Local Privilege Escalation CVSS 3.1HIGH 7.8
  • TI-2026-58387 Heap corruption via OCSP request double free from crafted multi-URL certificate in TLS client CVSS 4.0HIGH 8.2
  • TI-2023-00414 MongoDB client C Driver may infinitely loop when validating certain BSON input data CVSS 3.1HIGH 7.5
  • TI-2026-58386 Silent field truncation via unchecked int cast of huge JSON string values in JSON-to-BSON parser CVSS 4.0MEDIUM 6.3
See all 20 →

Sources

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