Listen to this Post
CVE-2026-13063 is a medium-severity vulnerability affecting MongoDB Server versions 8.2.x before 8.2.12 and 8.3.x before 8.3.7. The flaw resides in the libmongocrypt library, which is responsible for encryption and decryption operations during aggregation pipeline execution. An authenticated user with standard read/write privileges can cause the mongod process to terminate due to an out-of-memory (OOM) condition by sending a specially crafted aggregation command.
The root cause is insufficient validation of payload-supplied values within libmongocrypt. When a malicious aggregation command is submitted, the library fails to properly validate input parameters that control memory allocation behavior. User-controlled input directly influences the amount of memory allocated during query execution, allowing an attacker to trigger an excessively large memory allocation that quickly exhausts available system resources. This leads to uncontrolled resource consumption, classified under CWE-400, and has also been associated with CWE-190 (Integer Overflow or Wraparound).
The attack vector is network-based with low attack complexity, requiring no user interaction. The attacker only needs low privileges—standard read/write access to the database—making this vulnerability accessible to any authenticated database user. Exploitation results in a denial-of-service condition where the mongod process crashes, causing database unavailability, potential data loss during restarts, and significant operational downtime. The vulnerability has no impact on confidentiality or integrity, and the availability impact is rated as LOW.
CVSS 3.1 base score is 4.3 (MEDIUM) with vector CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L. CVSS 4.0 vector is CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N. The vulnerability was published on July 22, 2026, and last modified on July 23, 2026. No active exploitation has been reported as of the publication date.
The issue is particularly concerning for deployments with encryption-at-rest configurations where libmongocrypt is heavily utilized. Remediation requires upgrading to fixed versions 8.2.12, 8.3.7, or later. Until patching is complete, organizations should implement additional monitoring for unusual memory allocation patterns and limit user privileges where possible.
DailyCVE Form:
Platform: MongoDB Server
Version: 8.2.x, 8.3.x
Vulnerability: Input Validation Flaw
Severity: Medium (CVSS 4.3)
date: July 22, 2026
Prediction: August 19, 2026
What Undercode Say:
Analytics:
- EPSS score: 0.21% (low probability of exploitation)
- Exploit availability: None reported
- KEV status: Not listed
- Attack complexity: Low
- Privileges required: Low (authenticated user)
- User interaction: None
- Confidentiality impact: None
- Integrity impact: None
- Availability impact: Low
Bash commands to check version and apply patch:
Check current MongoDB version mongod --version For Debian/Ubuntu (update to fixed version) sudo apt-get update sudo apt-get install mongodb-org=8.2.12 For RHEL/CentOS sudo yum update mongodb-org sudo yum install mongodb-org-8.2.12 Verify upgrade mongod --version | grep "db version" Restart service sudo systemctl restart mongod sudo systemctl status mongod
Exploit:
An authenticated attacker with read/write privileges sends a crafted aggregation command containing a payload with an excessively large or malformed value that controls memory allocation in libmongocrypt. The library fails to validate this value, leading to an integer overflow or wraparound (CWE-190) that results in an allocation of an unexpectedly large memory block. This consumes all available system memory, causing the mongod process to crash due to an out-of-memory condition. The attack requires only network access and can be executed remotely.
Protection:
- Upgrade MongoDB Server to version 8.2.12, 8.3.7, or later
- Update libmongocrypt library to the latest patched version
- Implement input validation controls within aggregation pipelines
- Monitor for unusual memory allocation patterns and set resource limits
- Restrict user privileges to the minimum required for database operations
- Apply network segmentation to limit exposure of MongoDB instances
- Deploy rate limiting and query size restrictions on aggregation commands
Impact:
- Denial of service: mongod process terminates, rendering the database unavailable
- Operational downtime: manual intervention required to restart the mongod process
- Potential data loss during unclean process restarts
- Disruption of business operations dependent on database availability
- Monitoring systems may generate false positive alerts about resource exhaustion
- No impact on data confidentiality or integrity
- Affects environments with encryption-at-rest configurations where libmongocrypt is used
🎯Let’s Practice Exploiting & Learn Patching For Free:
🎓 Live Courses & Certifications:
Join Undercode Academy for Verified Certifications
🚀 Request a Custom Project:
Secure, high-velocity infrastructure and disruptive technological engineering. Contact our engineering team for high-tier development and proprietary systems:
[email protected]
💎 Smart Architecture | 🛡️ Secure by Design | ⭐ Trusted by Thousands
Sources:
Reported By: nvd.nist.gov
Extra Source Hub:
Undercode
