Answer in brief
CVE-2026-88035 records a Medium severity (CVSS 5.7) vulnerability in Heap buffer overflow via wrapped size check during SASL username canonicalization in MongoDB C Driver. The current sources do not mark it as known exploited. The current feed maps MongoDB/C Driver (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 5.7. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps MongoDB/C Driver (generic). Check affected ranges and fixed versions before updating.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:a:mongodb:c_driver:*:*:*:*:*:mongodb:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| MongoDB/C Drivergeneric | >=2.2.0 <2.5.3 | 2.5.3 |
Published upstream
Sep 10, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 16, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 10, 2026
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.
Quoted source text, attributed separately from HOL analysis.