CVE-2025-13878
📋 TL;DR
A denial-of-service vulnerability in BIND DNS servers where malformed BRID/HHIT records cause the named process to crash. This affects BIND 9 installations running vulnerable versions, primarily impacting DNS server availability.
💻 Affected Systems
- ISC BIND 9
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
DNS service outage leading to complete loss of DNS resolution for dependent systems and applications.
Likely Case
Intermittent DNS service disruptions requiring manual restart of BIND processes.
If Mitigated
Minimal impact with proper network segmentation and monitoring to detect and restart crashed services.
🎯 Exploit Status
Exploitation requires sending malformed DNS records to vulnerable servers, which is straightforward for attackers with network access.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 9.18.44, 9.20.18, 9.21.17
Vendor Advisory: https://kb.isc.org/docs/cve-2025-13878
Restart Required: Yes
Instructions:
1. Download patched version from ISC downloads page. 2. Stop BIND service. 3. Install updated BIND package. 4. Restart BIND service. 5. Verify service is running and responding to queries.
🔧 Temporary Workarounds
Rate Limiting
linuxImplement DNS query rate limiting to reduce impact of malicious queries
Add 'rate-limit { responses-per-second 10; };' to named.conf options
Response Policy Zones
linuxUse RPZ to block queries containing BRID/HHIT records
Configure RPZ zone with policy to drop BRID/HHIT queries
🧯 If You Can't Patch
- Implement strict network ACLs to limit DNS queries to trusted sources only
- Deploy monitoring with automatic restart scripts for BIND service crashes
🔍 How to Verify
Check if Vulnerable:
Check BIND version with 'named -v' or 'rpm -q bind' and compare against affected versionsCheck Version:
named -vVerify Fix Applied:
Verify installed version is 9.18.44, 9.20.18, or 9.21.17 or higher📡 Detection & Monitoring
Log Indicators:
- named process crash logs
- unexpected termination messages in system logs
- DNS query timeouts in application logs
Network Indicators:
- Unusual volume of BRID/HHIT record queries
- DNS service unresponsiveness
SIEM Query:
source="bind" AND (event="crash" OR event="terminated")