// For flags

CVE-2020-8616

BIND does not sufficiently limit the number of fetches performed when processing referrals

Severity Score

8.6
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

1
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

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.

Un actor malicioso que explota intencionalmente esta falta de limitación efectiva en el número de recuperaciones realizadas cuando se procesan referencias puede, mediante el uso de referencias especialmente diseñadas, causar que un servidor recurrente emita una gran cantidad de recuperaciones en un intento de procesar la referencia. Esto tiene al menos dos efectos potenciales: el rendimiento del servidor recurrente puede estar potencialmente afectado por el trabajo adicional requerido para realizar estas recuperaciones, y el atacante puede explotar este comportamiento para utilizar el servidor recurrente como un reflector en un ataque de reflexión con un alto factor de amplificación

A flaw was found in BIND, where it does not sufficiently limit the number of fetches that can be performed while processing a referral response. This flaw allows an attacker to cause a denial of service attack. The attacker can also exploit this behavior to use the recursing server as a reflector in a reflection attack with a high amplification factor.

*Credits: ISC would like to thank Lior Shafir and Yehuda Afek of Tel Aviv University and Anat Bremler-Barr of Interdisciplinary Center (IDC) Herzliya for discovering and reporting this issue.
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Changed
Confidentiality
None
Integrity
None
Availability
High
Attack Vector
Network
Attack Complexity
Low
Authentication
None
Confidentiality
None
Integrity
None
Availability
Partial
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2020-02-05 CVE Reserved
  • 2020-05-19 CVE Published
  • 2024-09-12 EPSS Updated
  • 2024-09-16 CVE Updated
  • 2024-09-16 First Exploit
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
CWE
  • CWE-400: Uncontrolled Resource Consumption
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Isc
Search vendor "Isc"
Bind
Search vendor "Isc" for product "Bind"
>= 9.0.0 <= 9.11.18
Search vendor "Isc" for product "Bind" and version " >= 9.0.0 <= 9.11.18"
-
Affected
Isc
Search vendor "Isc"
Bind
Search vendor "Isc" for product "Bind"
>= 9.12.0 <= 9.12.4
Search vendor "Isc" for product "Bind" and version " >= 9.12.0 <= 9.12.4"
-
Affected
Isc
Search vendor "Isc"
Bind
Search vendor "Isc" for product "Bind"
>= 9.13.0 <= 9.13.7
Search vendor "Isc" for product "Bind" and version " >= 9.13.0 <= 9.13.7"
-
Affected
Isc
Search vendor "Isc"
Bind
Search vendor "Isc" for product "Bind"
>= 9.14.0 <= 9.14.11
Search vendor "Isc" for product "Bind" and version " >= 9.14.0 <= 9.14.11"
-
Affected
Isc
Search vendor "Isc"
Bind
Search vendor "Isc" for product "Bind"
>= 9.15.0 <= 9.15.6
Search vendor "Isc" for product "Bind" and version " >= 9.15.0 <= 9.15.6"
-
Affected
Isc
Search vendor "Isc"
Bind
Search vendor "Isc" for product "Bind"
>= 9.16.0 <= 9.16.2
Search vendor "Isc" for product "Bind" and version " >= 9.16.0 <= 9.16.2"
-
Affected
Isc
Search vendor "Isc"
Bind
Search vendor "Isc" for product "Bind"
>= 9.17.0 <= 9.17.1
Search vendor "Isc" for product "Bind" and version " >= 9.17.0 <= 9.17.1"
-
Affected
Isc
Search vendor "Isc"
Bind
Search vendor "Isc" for product "Bind"
9.12.4
Search vendor "Isc" for product "Bind" and version "9.12.4"
p1
Affected
Isc
Search vendor "Isc"
Bind
Search vendor "Isc" for product "Bind"
9.12.4
Search vendor "Isc" for product "Bind" and version "9.12.4"
p2
Affected
Isc
Search vendor "Isc"
Bind
Search vendor "Isc" for product "Bind"
9.9.3
Search vendor "Isc" for product "Bind" and version "9.9.3"
s1, supported_preview
Affected
Isc
Search vendor "Isc"
Bind
Search vendor "Isc" for product "Bind"
9.10.5
Search vendor "Isc" for product "Bind" and version "9.10.5"
s1, supported_preview
Affected
Isc
Search vendor "Isc"
Bind
Search vendor "Isc" for product "Bind"
9.10.7
Search vendor "Isc" for product "Bind" and version "9.10.7"
s1, supported_preview
Affected
Isc
Search vendor "Isc"
Bind
Search vendor "Isc" for product "Bind"
9.11.3
Search vendor "Isc" for product "Bind" and version "9.11.3"
s1, supported_preview
Affected
Isc
Search vendor "Isc"
Bind
Search vendor "Isc" for product "Bind"
9.11.5
Search vendor "Isc" for product "Bind" and version "9.11.5"
s3, supported_preview
Affected
Isc
Search vendor "Isc"
Bind
Search vendor "Isc" for product "Bind"
9.11.5
Search vendor "Isc" for product "Bind" and version "9.11.5"
s5, supported_preview
Affected
Isc
Search vendor "Isc"
Bind
Search vendor "Isc" for product "Bind"
9.11.6
Search vendor "Isc" for product "Bind" and version "9.11.6"
s1, supported_preview
Affected
Isc
Search vendor "Isc"
Bind
Search vendor "Isc" for product "Bind"
9.11.7
Search vendor "Isc" for product "Bind" and version "9.11.7"
s1, supported_preview
Affected
Isc
Search vendor "Isc"
Bind
Search vendor "Isc" for product "Bind"
9.11.8
Search vendor "Isc" for product "Bind" and version "9.11.8"
s1, supported_preview
Affected
Debian
Search vendor "Debian"
Debian Linux
Search vendor "Debian" for product "Debian Linux"
9.0
Search vendor "Debian" for product "Debian Linux" and version "9.0"
-
Affected
Debian
Search vendor "Debian"
Debian Linux
Search vendor "Debian" for product "Debian Linux"
10.0
Search vendor "Debian" for product "Debian Linux" and version "10.0"
-
Affected