CVE-2026-6811 PHP Stack Exhaustion
Attackers can crash applications using the MongoDB PHP driver by sending deeply nested BSON documents from non-MongoDB sources.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-6811?
CVE-2026-6811 is a medium-severity denial of service vulnerability in MongoDB Inc. PHP Driver, published on 14 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
Stack exhaustion vulnerability in the MongoDB PHP driver can cause application crashes when processing deeply nested BSON documents in unusual circumstances when the source of these BSON documents is not MongoDB Server.
Weakness: CWE-674
Which versions are affected by CVE-2026-6811?
It affects 1 product.
Products include Mongodb Php Driver.
How do I fix CVE-2026-6811?
Upgrade to a fixed version.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-6811 being exploited?
There is no known exploitation of CVE-2026-6811 in the wild and no public exploit code.
Other vulnerabilities in MongoDB Inc. PHP Driver
- CVE-2026-81525 Cross-tenant database retargeting via dot/NUL injection in namespace strings in the PHP Driver
- CVE-2026-84968 Heap out-of-bounds read via corrupt nested BSON in field path error message
- CVE-2026-106436 Application denial of service and data truncation via unchecked BSON append failures in MongoDB PHP Driver
- CVE-2026-106432 Heap buffer overflow via 32-bit string-length truncation in MongoDB PHP Driver
Sources
Also known as DEBIAN-CVE-2026-6811, GHSA-vc69-vr6f-4x67, UBUNTU-CVE-2026-6811.