VulnerabilityModified
CVE-2017-2624
If the cookie is correct, it is allowed to attach to the Xorg session.
HIGH 7.0EPSS 0.67%
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.67%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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 3.0
- 7.0 HIGHCVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.67% probability · 50th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-385, CWE-200
- Affected
- x.org/x server · debian/debian linux
- Source
- secalert@redhat.com
References
- http://www.securityfocus.com/bid/96480Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1037919Third Party Advisory, VDB Entry
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2017-2624Exploit, Issue Tracking, Third Party Advisory
- https://gitlab.freedesktop.org/xorg/xserver/commit/d7ac755f0b618eb1259d93c8a16ec6e39a18627cPatch, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2017/11/msg00032.htmlThird Party Advisory
- https://security.gentoo.org/glsa/201704-03Third Party Advisory
- https://security.gentoo.org/glsa/201710-30Third Party Advisory
- https://www.x41-dsec.de/lab/advisories/x41-2017-001-xorg/Exploit, Third Party Advisory
- http://www.securityfocus.com/bid/96480Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1037919Third Party Advisory, VDB Entry
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2017-2624Exploit, Issue Tracking, Third Party Advisory
- https://gitlab.freedesktop.org/xorg/xserver/commit/d7ac755f0b618eb1259d93c8a16ec6e39a18627cPatch, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2017/11/msg00032.htmlThird Party Advisory
- https://security.gentoo.org/glsa/201704-03Third Party Advisory
- https://security.gentoo.org/glsa/201710-30Third Party Advisory
- https://www.x41-dsec.de/lab/advisories/x41-2017-001-xorg/Exploit, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.