CVE-2015-2689

Publication date 24 January 2020

Last updated 24 July 2024

Ubuntu priority

Cvss 3 Severity Score

Tor before 0.2.4.26 and 0.2.5.x before 0.2.5.11 does not properly handle pending-connection resolve states during periods of high DNS load, which allows remote attackers to cause a denial of service (assertion failure and daemon exit) via crafted packets.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
tor	17.04 zesty	Not affected
	16.10 yakkety	Not affected
	16.04 LTS xenial	Not affected
	15.10 wily	Not affected
	15.04 vivid	Fixed 0.2.5.12-1build0.15.04.1
	14.10 utopic	Ignored end of life
	14.04 LTS trusty	Fixed 0.2.4.27-1build0.14.04.1
	12.04 LTS precise	Ignored end of life
	10.04 LTS lucid	Not in release

Notes

sbeattie

DoS due to DNS triggering an abort

Severity score breakdown

Parameter	Value
Base score	7.5 · High
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	High
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H