Description
PowerDNS Recursor before 3.6.2 does not limit delegation chaining, which allows remote attackers to cause a denial of service ("performance degradations") via a large or infinite number of referrals, as demonstrated by resolving domains hosted by ezdns.it.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | pdns-recursor | 3.6.2-1 | — |
| Debian 13 | pdns-recursor | 3.6.2-1 | — |
| Debian 12 | pdns-recursor | 3.6.2-1 | — |
| Debian 7 | pdns-recursor | 3.3-3+deb7u1 | DSA-3096-1 |
| Debian 6.0 | pdns-recursor | 3.2-4+deb6u1 | DLA-104-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 14.04 LTS | pdns-recursor | 3.5.3-1ubuntu0.1 | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | pdns-recursor | 4.0.3-1.2 | openSUSE-SU-2024:10537-1 |
Advisories 3
- DSA-3096-1 pdns-recursor - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-104-1 pdns-recursor - security update Debian Security (DSA / DLA) · Mar 9, 2026
- openSUSE-SU-2024:10537-1 pdns-recursor-4.0.3-1.2 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
References
- http://doc.powerdns.com/md/security/powerdns-advisory-2014-02/
- DSA-3096 vendor-advisory
- 1031310 vdb-entry
- http://cert.ssi.gouv.fr/site/CERTFR-2014-AVI-512/index.html
- 71545 vdb-entry
- VU#264212 third-party-advisory