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Fencer Intel
medium 6.2

CVE-2026-106437 json

Out-of-bounds read and write via undersized BSON buffer reservation in MongoDB C Driver

published last mo. modified 13d ago also EUVD-2026-95153

cvss
6.2
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.1%
EPSS 0.1% chance of exploitation in 30 days, percentile 2%
public exploits
0
none known

Summary

The BSON buffer-reservation API in the MongoDB C Driver can record a length smaller than the five-byte BSON minimum. Later append or comparison operations can underflow unsigned length calculations and read or write outside the document buffer. An actor who can influence the length supplied by an embedding application can cause the application to terminate or read or corrupt adjacent process memory. Reaching this issue requires the application to pass an undersized value to bson_reserve_buffer and then perform an affected operation.

Patch / fix

  • MongoDB C Driver 1.30.13, 2.5.6
  • mongo-c-driver Debian 14 2.5.6-1

debian advisories DEBIAN-CVE-2026-106437

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-106437 updated cvss 6.2

mongo-c-driver: mongo-c-driver: Denial of Service via integer underflow in bson_reserve_buffer

  • Red Hat All currently supported Red Hat products
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
last mo.

Exploit prediction

0.13% chance of exploitation in the next 30 days, higher than 2% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 4.0 5.9 CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N
CNA 3.1 6.2 CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H
CNA 4.0 5.9 CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:H/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
NVD 3.1 7.4 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

Affected products

  • MongoDB C Driver

Classification

Weakness
  • CWE-191 Integer Underflow (Wrap or Wraparound)

References

Sources

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