High severity · published Jul 27, 2018
CVE-2017-2624
It was found that xorg-x11-server before 1.19.0 including uses memcmp() to check the received MIT cookie against a series of valid cookies
7.0
CVSS
0.7%
EPSS
No
On KEV
Description
It was found that xorg-x11-server before 1.19.0 including uses memcmp() to check the received MIT cookie against a series of valid cookies. If the cookie is correct, it is allowed to attach to the Xorg session. Since most memcmp() implementations return after an invalid byte is seen, this causes a time difference between a valid and invalid byte, which could allow an efficient brute force attack.
CVSS vector
CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 53% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
7.0 · source: NVD
XS
X Server · X.org
through 1.19.4 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2017-2624
CVE.org
https://www.cve.org/CVERecord?id=CVE-2017-2624
Third Party Advisory
http://www.securityfocus.com/bid/96480
Third Party Advisory
http://www.securitytracker.com/id/1037919
Exploit
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2017-2624
Patch
https://gitlab.freedesktop.org/xorg/xserver/commit/d7ac755f0b618eb1259d93c8a16ec6e39a18627c
Third Party Advisory
https://lists.debian.org/debian-lts-announce/2017/11/msg00032.html
Third Party Advisory
https://security.gentoo.org/glsa/201704-03
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