certfr_avis - certfr-2019-avi-585

CERTFR-2019-AVI-585

Vulnerability from certfr_avis

Une vulnérabilité a été découverte dans BIND. Elle permet à un attaquant de provoquer un déni de service à distance et un contournement de la politique de sécurité.

Solution

Se référer au bulletin de sécurité de l'éditeur pour l'obtention des correctifs (cf. section Documentation).

None

Impacted products

Vendor	Product	Description
ISC	BIND	BIND versions 9.15.x antérieures à 9.15.6
ISC	BIND	BIND versions antérieures à 9.11.13
ISC	BIND	BIND versions 9.12.x et 9.14.x antérieures à 9.14.8

References

Title

Publication Time

CVE-2019-6477 (GCVE-0-2019-6477)

Vulnerability from cvelistv5

Published

2019-11-26 16:11

Modified

2024-09-16 16:47

Severity ?

7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CWE

By design, BIND is intended to limit the number of TCP clients that can be connected at any given time. The update to this functionality introduced by CVE-2018-5743 changed how BIND calculates the number of concurrent TCP clients from counting the outstanding TCP queries to counting the TCP client connections. On a server with TCP-pipelining capability, it is possible for one TCP client to send a large number of DNS requests over a single connection. Each outstanding query will be handled internally as an independent client request, thus bypassing the new TCP clients limit. 9.11.6-P1 -> 9.11.12, 9.12.4-P1 -> 9.12.4-P2, 9.14.1 -> 9.14.7, and versions 9.11.5-S6 -> 9.11.12-S1 of BIND 9 Supported Preview Edition. Versions 9.15.0 -> 9.15.5 of the BIND 9.15 development branch are also affected.

Summary

With pipelining enabled each incoming query on a TCP connection requires a similar resource allocation to a query received via UDP or via TCP without pipelining enabled. A client using a TCP-pipelined connection to a server could consume more resources than the server has been provisioned to handle. When a TCP connection with a large number of pipelined queries is closed, the load on the server releasing these multiple resources can cause it to become unresponsive, even for queries that can be answered authoritatively or from cache. (This is most likely to be perceived as an intermittent server problem).

References

URL

Tags

	https://kb.isc.org/docs/cve-2019-6477	x_refsource_CONFIRM
	https://www.synology.com/security/advisory/Synology_SA_19_39	x_refsource_CONFIRM
	https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XGURMGQHX45KR4QDRCSUQHODUFOGNGAN/	vendor-advisory, x_refsource_FEDORA
	https://support.f5.com/csp/article/K15840535?utm_source=f5support&amp%3Butm_medium=RSS	x_refsource_CONFIRM
	https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L3DEMNZMKR57VQJCG5ZN55ZGTQRL2TFQ/	vendor-advisory, x_refsource_FEDORA
	https://www.debian.org/security/2020/dsa-4689	vendor-advisory, x_refsource_DEBIAN
	http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00041.html	vendor-advisory, x_refsource_SUSE
	http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00044.html	vendor-advisory, x_refsource_SUSE

Impacted products

	Vendor	Product	Version
	ISC	BIND9	Version: 9.11.6-P1 -> 9.11.12, 9.12.4-P1 -> 9.12.4-P2, 9.14.1 -> 9.14.7, and versions 9.11.5-S6 -> 9.11.12-S1 of BIND 9 Supported Preview Edition. Versions 9.15.0 -> 9.15.5 of the BIND 9.15 development branch are also affected

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
Confirmed: The vulnerability is confirmed from an analyst perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
Patched: This vulnerability was successfully patched by the user reporting the sighting.
Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
Not confirmed: The user expresses doubt about the veracity of the vulnerability.
Not patched: This vulnerability was not successfully patched by the user reporting the sighting.

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