Insecure source port usage for DNS queries in Graylog
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- None · Low · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub. Impact type from CWE-345.
Summary
Graylog is a free and open log management platform. Graylog makes use of only one single source port for DNS queries. Graylog binds a single socket for outgoing DNS queries and while that socket is bound to a random port number it is never changed again. This goes against recommended practice since 2008, when Dan Kaminsky discovered how easy is to carry out DNS cache poisoning attacks. In order to prevent cache poisoning with spoofed DNS responses, it is necessary to maximise the uncertainty in the choice of a source port for a DNS query. Although unlikely in many setups, an external attacker could inject forged DNS responses into a Graylog's lookup table cache. In order to prevent this, it is at least recommendable to distribute the DNS queries through a pool of distinct sockets, each of them with a random source port and renew them periodically. This issue has been addressed in versions 5.0.9 and 5.1.3. Users are advised to upgrade. There are no known workarounds for this issue.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Graylog2 | graylog2-server | before 5.0.9; 5.1.0 to before 5.1.3 | 5.0.9, 5.1.3 | Patch available | CNA |
| — | org.graylog2:graylog2-server (Maven) | 5.1.0 to before 5.1.3 | 5.1.3 | Patch available | GHSA-g96c-x7rh-99r3 |
| — | org.graylog2:graylog2-server (Maven) | before 5.0.9 | 5.0.9 | Patch available | GHSA-g96c-x7rh-99r3 |
- graylog2-server VendorGraylog2 Affected before 5.0.9; 5.1.0 to before 5.1.3 Fixed in 5.0.9, 5.1.3 Patch available CNA
- org.graylog2:graylog2-server (Maven) Vendor— Affected 5.1.0 to before 5.1.3 Fixed in 5.1.3 Patch available GHSA-g96c-x7rh-99r3
- org.graylog2:graylog2-server (Maven) Vendor— Affected before 5.0.9 Fixed in 5.0.9 Patch available GHSA-g96c-x7rh-99r3
Remediation
- Fix · CNA graylog2-server (Graylog2) Fixed in 5.0.9, 5.1.3
- Fix · GHSA-g96c-x7rh-99r3 org.graylog2:graylog2-server (Maven) Fixed in 5.1.3 Advisory →
- Fix · GHSA-g96c-x7rh-99r3 org.graylog2:graylog2-server (Maven) Fixed in 5.0.9 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2023-41045
- 2026-10-03 Alias added: GHSA-g96c-x7rh-99r3
References
Patch 2
More Graylog2 Graylog vulnerabilities
- TI-2024-16341 graylog2-server vulnerable to instantiation of arbitrary classes triggered by API request CVSS 3.1HIGH 8.8
- TI-2026-01133 Incorrect management of session invalidation vulnerability in Graylog Web Interface CVSS 4.0CRITICAL 9.3
- TI-2023-21667 User session is still usable after logout in graylog2-server CVSS 3.1LOW 3.1
- TI-2021-15624 A Session ID leak in the audit log in Graylog before 4.1.2 allows attackers to escalate… CVSS 3.1CRITICAL 9.8
- TI-2021-15623 A Session ID leak in the DEBUG log file in Graylog before 4.1.2 allows attackers to… CVSS 3.1CRITICAL 9.8
- TI-2025-33099 Graylog vulnerable to privilege escalation through API tokens CVSS 4.0HIGH 8.8
Sources
- CVE-2023-41045 · CVE Program
- CVE-2023-41045 · NVD
- FIRST EPSS
- GHSA-g96c-x7rh-99r3 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences