CVE-2026-84969 (GCVE-0-2026-84969)

Vulnerability from cvelistv5 – Published: 2026-09-03 14:59 – Updated: 2026-09-03 15:08
VLAI
Title
Heap overflow via truncated base64 encoding of binary fields in length-limited JSON output
Summary
A memory-handling error in the BSON-to-JSON conversion helpers of the MongoDB C Driver can write a small number of bytes past the end of a heap buffer when a binary field is encoded and the output is cut short at a caller-configured length limit. A party who supplies the document content, with no privileges on the application that links the driver, may cause a small amount of data outside the intended buffer to be altered.
Severity
6.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
3.7 (Low)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-03 15:07 UTC
CWE
Assigner
mongodb CNA under the mitre root
CNA scorecard C 70/100 over 222 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
MongoDB C Driver Affected: 1.30.0 , < 1.30.9 (semver)
Affected: 2.0.0 , < 2.5.2 (semver)
guessed Create a notification for this product.
Show details on NVD website
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