Interaction between the sks-keyserver code through 1.2.0 of the SKS keyserver network, and GnuPG through 2.2.16, makes it risky to have a GnuPG keyserver configuration line referring to a host on the SKS keyserver network. Retrieving data from this network may cause a persistent denial of service, because of a Certificate Spamming Attack.
Weakness
The product does not validate, or incorrectly validates, a certificate.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Gnupg | Gnupg | * | 2.2.16 (including) |
| Sks_keyserver | Sks_keyserver_project | * | 1.2.0 (including) |
| Red Hat Enterprise Linux 8 | RedHat | gnupg2-0:2.2.20-2.el8 | * |
| Gnupg | Ubuntu | precise/esm | * |
| Gnupg | Ubuntu | trusty/esm | * |
| Gnupg | Ubuntu | xenial | * |
| Gnupg2 | Ubuntu | bionic | * |
| Gnupg2 | Ubuntu | disco | * |
| Gnupg2 | Ubuntu | eoan | * |
| Gnupg2 | Ubuntu | esm-infra/bionic | * |
| Gnupg2 | Ubuntu | esm-infra/xenial | * |
| Gnupg2 | Ubuntu | upstream | * |
| Gnupg2 | Ubuntu | xenial | * |
| Sks | Ubuntu | bionic | * |
| Sks | Ubuntu | cosmic | * |
| Sks | Ubuntu | disco | * |
| Sks | Ubuntu | eoan | * |
| Sks | Ubuntu | focal | * |
| Sks | Ubuntu | trusty | * |
| Sks | Ubuntu | upstream | * |
| Sks | Ubuntu | xenial | * |
Potential Mitigations
Related Attack Patterns
References
- http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00039.html
- https://gist.github.com/rjhansen/67ab921ffb4084c865b3618d6955275f
- https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E
- https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E
- https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772%40%3Cdev.mina.apache.org%3E
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AUK2YRO6QIH64WP2LRA5D4LACTXQPPU4/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CP4ON34YEXEZDZOXXWV43KVGGO6WZLJ5/
- https://lists.gnupg.org/pipermail/gnupg-announce/2019q3/000439.html
- https://support.f5.com/csp/article/K08654551
- https://support.f5.com/csp/article/K08654551?utm_source=f5support\u0026amp%3Butm_medium=RSS
- https://twitter.com/lambdafu/status/1147162583969009664
- http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00039.html
- https://gist.github.com/rjhansen/67ab921ffb4084c865b3618d6955275f
- https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E
- https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E
- https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772%40%3Cdev.mina.apache.org%3E
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AUK2YRO6QIH64WP2LRA5D4LACTXQPPU4/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CP4ON34YEXEZDZOXXWV43KVGGO6WZLJ5/
- https://lists.gnupg.org/pipermail/gnupg-announce/2019q3/000439.html
- https://support.f5.com/csp/article/K08654551
- https://support.f5.com/csp/article/K08654551?utm_source=f5support\u0026amp%3Butm_medium=RSS
- https://twitter.com/lambdafu/status/1147162583969009664