CVE-2020-8617
Using a specially-crafted message, an attacker may potentially cause a BIND server to reach an inconsistent state if the attacker knows (or successfully guesses) the name of a TSIG key used by the server.
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 93.3%, higher than 100% of all known CVEs. Patch or mitigate before the next change window.
Description
Using a specially-crafted message, an attacker may potentially cause a BIND server to reach an inconsistent state if the attacker knows (or successfully guesses) the name of a TSIG key used by the server. Since BIND, by default, configures a local session key even on servers whose configuration does not otherwise make use of it, almost all current BIND servers are vulnerable. In releases of BIND dating from March 2018 and after, an assertion check in tsig.c detects this inconsistent state and deliberately exits. Prior to the introduction of the check the server would continue operating in an inconsistent state, with potentially harmful results.
- CVSS 3.1
- 5.9 MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 93.33% probability · 100th percentile
- Public exploits
- 1 in Exploit-DB · first 20 May 2020
- CISA KEV
- Not listed
- Weakness
- CWE-617
- Affected
- isc/bind · debian/debian linux · fedoraproject/fedora · opensuse/leap · canonical/ubuntu linux
- Source
- security-officer@isc.org
EPSS 93.3% since 3 November 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
Public exploits (1)
Entries in Exploit-DB that cite this CVE. Links go to the Exploit-DB page and to the file in the public repository; nothing is hosted here. A verified tick means the Exploit-DB team confirmed the exploit works against the stated version.
References
- http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00041.htmlMailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00044.htmlMailing List, Third Party Advisory
- http://packetstormsecurity.com/files/157836/BIND-TSIG-Denial-Of-Service.htmlThird Party Advisory, VDB Entry
- http://www.openwall.com/lists/oss-security/2020/05/19/4Mailing List, Patch, Third Party Advisory
- https://kb.isc.org/docs/cve-2020-8617Patch, Vendor Advisory
- https://lists.debian.org/debian-lts-announce/2020/05/msg00031.htmlMailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JKJXVBOKZ36ER3EUCR7VRB7WGHIIMPNJ/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WOGCJS2XQ3SQNF4W6GLZ73LWZJ6ZZWZI/
- https://security.netapp.com/advisory/ntap-20200522-0002/Third Party Advisory
- https://usn.ubuntu.com/4365-1/Third Party Advisory
- https://usn.ubuntu.com/4365-2/Third Party Advisory
- https://www.debian.org/security/2020/dsa-4689Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00041.htmlMailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00044.htmlMailing List, Third Party Advisory
- http://packetstormsecurity.com/files/157836/BIND-TSIG-Denial-Of-Service.htmlThird Party Advisory, VDB Entry
- http://www.openwall.com/lists/oss-security/2020/05/19/4Mailing List, Patch, Third Party Advisory
- https://kb.isc.org/docs/cve-2020-8617Patch, Vendor Advisory
- https://lists.debian.org/debian-lts-announce/2020/05/msg00031.htmlMailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JKJXVBOKZ36ER3EUCR7VRB7WGHIIMPNJ/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WOGCJS2XQ3SQNF4W6GLZ73LWZJ6ZZWZI/
- https://security.netapp.com/advisory/ntap-20200522-0002/Third Party Advisory
- https://usn.ubuntu.com/4365-1/Third Party Advisory
- https://usn.ubuntu.com/4365-2/Third Party Advisory
- https://www.debian.org/security/2020/dsa-4689Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.