CVE-2021-44494 – This vulnerability allows attackers to cause de... (How to Fix)

Q: What is the severity of CVE-2021-44494?

CVE-2021-44494 has a CVSS score of 7.5 (HIGH). This vulnerability allows attackers to cause denial of service by crashing YottaDB or GT.M database systems through crafted input to ZRead commands. It affects all users running vulnerable versions of YottaDB (through r1.32) and FIS GT.M (through V7.0-000). The crash occurs due to a NULL pointer dereference when processing malicious input.

📋 TL;DR

This vulnerability allows attackers to cause denial of service by crashing YottaDB or GT.M database systems through crafted input to ZRead commands. It affects all users running vulnerable versions of YottaDB (through r1.32) and FIS GT.M (through V7.0-000). The crash occurs due to a NULL pointer dereference when processing malicious input.

💻 Affected Systems

Products:

YottaDB
FIS GT.M

Versions: YottaDB through r1.32, FIS GT.M through V7.0-000

Operating Systems: All supported platforms (Linux, UNIX variants)

Default Config Vulnerable: ⚠️ Yes

Notes: All installations using ZRead functionality are vulnerable regardless of configuration.

📦 What is this software?

Gt.m by Fisglobal

View all CVEs affecting Gt.m →

Yottadb by Yottadb

View all CVEs affecting Yottadb →

⚠️ Risk & Real-World Impact

🔴

Worst Case

Complete database service disruption leading to application downtime and data unavailability until service restart.

🟠

Likely Case

Service crashes requiring manual intervention to restart database processes, causing temporary service disruption.

🟢

If Mitigated

Minimal impact if proper input validation and network segmentation are implemented.

🌐 Internet-Facing: MEDIUM - Requires ZRead access which may be exposed through application interfaces.

🏢 Internal Only: MEDIUM - Internal attackers or compromised systems could exploit this vulnerability.

🎯 Exploit Status

Public PoC: ✅ No

Weaponized: UNKNOWN

Unauthenticated Exploit: ✅ No

Complexity: LOW

Exploitation requires ability to send crafted input to ZRead commands, typically requiring some level of access to the database interface.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: YottaDB r1.34+, FIS GT.M V7.0-002+

Vendor Advisory: http://tinco.pair.com/bhaskar/gtm/doc/articles/GTM_V7.0-002_Release_Notes.html

Restart Required: Yes

Instructions:

1. Download latest version from official sources. 2. Backup current installation. 3. Install updated version following vendor documentation. 4. Restart all database processes.

🔧 Temporary Workarounds

Input Validation

all

Implement strict input validation for all ZRead command inputs to reject malformed data.

# Application-level validation required - no system commands

Access Restriction

all

Restrict access to ZRead functionality to trusted users and systems only.

# Configure application-level access controls

🧯 If You Can't Patch

Implement network segmentation to isolate database systems from untrusted networks
Deploy application-level input validation and sanitization for all ZRead inputs

🔍 How to Verify

Check if Vulnerable:

Check installed version against affected ranges: YottaDB <= r1.32 or GT.M <= V7.0-000

Check Version:

$ydb_dist/mumps -run %XCMD 'write $zversion' or $gtm_dist/mumps -run %XCMD 'write $zversion'

Verify Fix Applied:

Confirm version is YottaDB r1.34+ or GT.M V7.0-002+ and test ZRead functionality with normal operations

📡 Detection & Monitoring

Log Indicators:

Database process crashes
Core dumps in database logs
ZRead command failures

Network Indicators:

Unusual patterns of ZRead requests
Multiple rapid connection attempts to database

SIEM Query:

source="database_logs" AND (event="crash" OR event="segfault") AND process="mumps"

📊 Metadata

CVE ID: CVE-2021-44494

CVSS v3 Score: 7.5 (HIGH)

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CWE: CWE-476

Published: April 15, 2022

Last Updated: November 21, 2024

🔗 References

http://tinco.pair.com/bhaskar/gtm/doc/articles/GTM_V7.0-002_Release_Notes.html Release Notes,Third Party Advisory
https://gitlab.com/YottaDB/DB/YDB/-/issues/828 Issue Tracking,Patch,Third Party Advisory
https://sourceforge.net/projects/fis-gtm/files/ Product,Third Party Advisory
http://tinco.pair.com/bhaskar/gtm/doc/articles/GTM_V7.0-002_Release_Notes.html Release Notes,Third Party Advisory
https://gitlab.com/YottaDB/DB/YDB/-/issues/828 Issue Tracking,Patch,Third Party Advisory
https://sourceforge.net/projects/fis-gtm/files/ Product,Third Party Advisory

📤 Share & Export

📄 Export Markdown 📋 Export JSON

🔗 Related Vulnerabilities

If you're affected by CVE-2021-44494, you might also want to check these: