CVE-2026-9740: MongoDB Server · Uncontrolled Recursion
Affects MongoDB ServerSource CVE Database V5
Not known to be exploited · CVSS 8.7 High · fixed in 8.3.3 : patch MongoDB Server soon.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 27% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 8.3.3, 8.2.10, 8.0.24 +1
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 9 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade MongoDB Server to 8.3.3, 8.2.10, 8.0.24 or 7.0.35.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| MongoDBMongoDB Server | Affected
| Fixed in
|
| MongoDBMongoDB Server | Affected
| Fixed in
|
| MongoDBMongoDB Server | Affected
| Fixed in
|
| MongoDBMongoDB Server | Affected
| Fixed in
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AI-suggested
If you cannot patch yet, consider restricting network access to MongoDB instances to trusted sources to reduce exposure to unauthenticated attacks.
Description
A vulnerability in MongoDB Server's BSON validation logic allows an unauthenticated user to crash the mongod process by sending a specially crafted message. The BSON validator's handling of certain nested binary data structures permits uncontrolled mutual recursion between validation functions, where each re-entry resets internal depth tracking.