MongoDB Go Driver: Denial of service via missing BSON array length validation
Summary
The MongoDB Go Driver, a library linked into Go applications, does not validate the declared length of a four-byte BSON array before using it. An unauthenticated actor who can supply malformed raw BSON data to an affected application can trigger a runtime panic. The panic can terminate an unprotected application process, causing a denial of service; no confidentiality or integrity impact has been identified.
Affected
- MongoDB Go Driver v2.0.0 through v2.9.1
- MongoDB Go Driver v1.1.0 and later according to the release notes; the exact affected v1 range is unclear
- Default configuration is unaffected according to the CNA record
Fixed in
- Go Driver v2.9.2 (fix in PR #2591, GODRIVER-4136)
- No fixed v1 release confirmed; Unknown.
Workaround
- No vendor workaround identified.
- Until you can upgrade, reject raw BSON data with a declared length below 5 bytes before it reaches Validate or the reader-based BSON functions. This is a suggestion from the research, not a vendor recommendation.
- Recovering from panics in your own code limits the impact but does not fix the bug.
Exploitation
- No evidence of exploitation in the wild found; no CISA KEV entry found.
- CISA SSVC: exploitation none, automatable no, technical impact partial.
- No public proof of concept for this CVE found.
Our recommendation
- Identify Go services that use the driver and check whether they pass untrusted raw BSON data to the affected functions.
- Upgrade affected v2 services to Go Driver v2.9.2 as soon as possible.
- Check v1 usage and the MongoDB advisory, since no v1 fix is confirmed.
- Monitor services for unexpected crashes or panics.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- MongoDB Jira GODRIVER-4136 jira.mongodb.org
- Go Driver releases github.com
- Go Driver v2.9.2 release github.com
- Go Driver pull request 2591 github.com
- Ubuntu security tracker CVE-2026-107325 ubuntu.com
- VulDB entry 415553 vuldb.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 1 Nov 2026, 16:50.
Original description (NVD)
Improper validation of a BSON array length in the MongoDB Go Driver can cause an out-of-bounds index and runtime panic when an application calls bson.RawArray.Validate or bsoncore.Array.Validate on a malformed four-byte array. An unauthenticated actor who can supply raw BSON array data to an affected application may terminate an unprotected application process, causing a denial of service. No confidentiality or integrity impact has been identified.
NVD references (1)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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