CVE-2026-1849: MongoDB Server · Uncontrolled Recursion
Affects MongoDB ServerSource CVE Database V5
Not known to be exploited · CVSS 7.1 High · fixed in 8.2.2 : patch MongoDB Server soon.
Data as of 26 Oct 2026, 07:57 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 24% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 8.2.2, 8.0.18, 7.0.29
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 10 Feb 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 2026-10-26.
What to do
Upgrade MongoDB Server to 8.2.2, 8.0.18 or 7.0.29.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| MongoDB IncMongoDB Server | Affected
| Fixed in
|
AI-suggested
1. Monitor MongoDB query logs for unusually deep or complex nested document expressions that could indicate attempts to exploit uncontrolled recursion. 2. Implement strict access controls and least privilege principles to limit which users can execute complex queries or expressions. 3. Use MongoDB's built-in resource limits and query execution timeouts to prevent runaway queries from consuming excessive memory. 4. Deploy application-level input validation to prevent untrusted or malformed input from triggering deep recursion in database queries. 5. 6. Consider upgrading to newer MongoDB versions if they include fixes or improved recursion depth checks. 7. In cloud or managed environments, coordinate with service providers to ensure they have mitigations in place. 8. Conduct regular stress and fuzz testing of database queries to identify potential recursion-related issues proactively. 9. Isolate critical MongoDB instances and implement redundancy and failover mechanisms to minimize downtime in case of exploitation.
Description
MongoDB Server may experience an out-of-memory failure while evaluating expressions that produce deeply nested documents. The issue arises in recursive functions because the server does not periodically check the depth of the expression.