CVE-2022-33989: dproxy-nexgen (aka dproxy nexgen) uses a static UDP source port (selected randomly only at boot time) in upstr
CVE-2022-33989 is a medium-severity flaw (CVSS 5.3) affecting dproxy-nexgen. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
dproxy-nexgen (aka dproxy nexgen) uses a static UDP source port (selected randomly only at boot time) in upstream queries sent to DNS resolvers. This allows DNS cache poisoning because there is not enough entropy to prevent traffic injection attacks.
Why this priority
- Public exploit reference
- Remotely exploitable, no login, no user action
No fix is published yet: follow the downgrade or mitigation steps.
Risk facts
| CVSS score | 5.3 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 1.0% (top 37%) |
| CISA exploited list | No |
| Weakness | CWE-331 |
| Published | 2022-08-15 |
| Last modified | 2026-06-17 |
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2022-33989?
dproxy-nexgen: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.
Is CVE-2022-33989 being exploited?
CVE-2022-33989 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2022-33989 affect?
CVE-2022-33989 affects dproxy-nexgen. Severity is medium (CVSS 5.3). dproxy-nexgen (aka dproxy nexgen) uses a static UDP source port (selected randomly only at boot time) in upstream queries sent to DNS resolvers. This allows DNS cache poisoning because there is not enough entropy to prevent traffic injectio
How urgent is CVE-2022-33989?
Priority 44/100. Public exploit reference; Remotely exploitable, no login, no user action
Related CVEs
- CVE-2022-33991 MEDIUM 5.3 MITIGATE dproxy-nexgen (aka dproxy nexgen) forwards and caches DNS queries with the CD (aka checking disabled) bit set
- CVE-2022-33990 HIGH 7.5 MITIGATE Misinterpretation of special domain name characters in dproxy-nexgen (aka dproxy nexgen) leads to cache poison
- CVE-2022-33988 HIGH 7.5 MITIGATE dproxy-nexgen (aka dproxy nexgen) re-uses the DNS transaction id (TXID) value from client queries, which allow