Vulnerability · Published May 19, 2020 · Assigned by isc
CVE-2020-8616BIND does not sufficiently limit the number of fetches performed when processing referrals
High 8.6
In plain English
A high-severity security flaw in BIND9 from ISC. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 10.9% (higher than 96% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
A malicious actor who intentionally exploits this lack of effective limitation on the number of fetches performed when processing referrals can, through the use of specially crafted referrals, cause a recursing server to issue a very large number of fetches in an attempt to process the referral. This has at least two potential effects: The performance of the recursing server can potentially be degraded by the additional work required to perform these fetches, and The attacker can exploit this behavior to use the recursing server as a reflector in a reflection attack with a high amplification factor.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.20 | bind | 9.14.12-r0 | ALPINE-CVE-2020-8616 |
| Alpine:v3.21 | bind | 9.14.12-r0 | ALPINE-CVE-2020-8616 |
| Alpine:v3.22 | bind | 9.14.12-r0 | ALPINE-CVE-2020-8616 |
| Alpine:v3.23 | bind | 9.14.12-r0 | ALPINE-CVE-2020-8616 |
| Alpine:v3.24 | bind | 9.14.12-r0 | ALPINE-CVE-2020-8616 |
| Debian:12 | bind9 | 1:9.16.3-1 | DEBIAN-CVE-2020-8616 |
| Debian:13 | bind9 | 1:9.16.3-1 | DEBIAN-CVE-2020-8616 |
| Debian:14 | bind9 | 1:9.16.3-1 | DEBIAN-CVE-2020-8616 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| ISC | BIND9 | 9.0.0 -> 9.11.18, 9.12.0 -> 9.12.4-P2, 9.14.0 -> 9.14.11, 9.16.0 -> 9.16.2, and releases 9.17.0 -> 9.17.1 of the 9.17 experimental development branch. All releases in the obsolete 9.13 and 9.15 development branches. All releases of BIND Supported Preview Edition from 9.9.3-S1 -> 9.11.18-S1 |
References
- https://kb.isc.org/docs/cve-2020-8616 x_refsource_CONFIRM
- http://www.nxnsattack.com x_refsource_MISC
- [oss-security] 20200519 Two vulnerabilities disclosed in BIND (CVE-2020-8616 and CVE-2020-8617) mailing-list, x_refsource_MLIST
- DSA-4689 vendor-advisory, x_refsource_DEBIAN
- https://security.netapp.com/advisory/ntap-20200522-0002/ x_refsource_CONFIRM
- USN-4365-2 vendor-advisory, x_refsource_UBUNTU
- https://www.synology.com/security/advisory/Synology_SA_20_12 x_refsource_CONFIRM
- USN-4365-1 vendor-advisory, x_refsource_UBUNTU
- [debian-lts-announce] 20200530 [SECURITY] [DLA 2227-1] bind9 security update mailing-list, x_refsource_MLIST
- FEDORA-2020-2d89cbcfd9 vendor-advisory, x_refsource_FEDORA
- FEDORA-2020-f9dcd4e9d5 vendor-advisory, x_refsource_FEDORA
- openSUSE-SU-2020:1699 vendor-advisory, x_refsource_SUSE
- openSUSE-SU-2020:1701 vendor-advisory, x_refsource_SUSE