CVE-2026-93394

low

A flaw in libmongoc's SCRAM authentication implementation caused the client to continue the authentication handshake and transmit the client proof even when a…

Vendor / product: Mongodb — c driver

A flaw in libmongoc's SCRAM authentication implementation caused the client to continue the authentication handshake and transmit the client proof even when a nonce mismatch was detected in the server's first message. An unauthorized party with a man-in-the-middle position could exploit this by injecting a crafted server-first-message containing a controlled salt and low iteration count, then capturing the resulting client proof to perform offline password cracking. This vulnerability is mitigated by TLS, which is standard in production deployments.

CVSS

3.7

3.7 (CVSS v3.1)

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

Severity source: NVD CVSS v3.1 (cna@mongodb.com)

Timeline (UTC)

Published: 2026-09-17 21:17

Modified: 2026-09-25 20:33

NVD status: Analyzed

Last synced 2 days ago

Verified against the source API 2026-10-27 06:54 UTC

Exploitation

Not listed in CISA KEV (as of last catalog sync)

Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

mongodb / c_driver ≥2.0.0 <2.3.2

Weakness classification (CWE)

CWE-303

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

No vendor advisory or patch reference tagged by NVD. Check the references below.

References

https://jira.mongodb.org/browse/CDRIVER-6315 cna@mongodb.com

Data sources

NVD CVE API 2.0 — fetched 2026-10-27 06:54 UTC · record ↗

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CVE-2026-93394

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Weakness classification (CWE)

Mitigation & advisories

References

Data sources

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