SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityUndergoing Analysis

CVE-2026-88035

A size check in the client-side authentication path of the MongoDB C Driver can wrap around, so an unusually large user-name value is accepted and copied past the end of a small buffer.

MEDIUM 5.7EPSS 0.10%

Does this matter?

Lower severity and a low EPSS score (0.10%). Track it; it rarely justifies an emergency change on its own.

Description

A size check in the client-side authentication path of the MongoDB C Driver can wrap around, so an unusually large user-name value is accepted and copied past the end of a small buffer. A party able to set the driver's connection settings may cause the application that embeds the driver to terminate unexpectedly. Reaching this code requires a build in which the optional external SASL authentication backend is present and a connection configured to use it.

CVSS 4.0
5.7 MEDIUMCVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/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/M
EPSS
0.10% probability · 1th percentile
CISA KEV
Not listed
Weakness
CWE-190
Source
cna@mongodb.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.