High severity · published Dec 17, 2021
CVE-2021-4009
A flaw was found in xorg-x11-server in versions before 21.1.2 and before 1.20.14
7.8
CVSS
0.6%
EPSS
No
On KEV
Description
A flaw was found in xorg-x11-server in versions before 21.1.2 and before 1.20.14. An out-of-bounds access can occur in the SProcXFixesCreatePointerBarrier function. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 49% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
9.0; 10.0; 11.0 · source: NVD
FE
Fedora · Fedoraproject
34; 35 · source: NVD
XS
X Server · X.org
before 1.20.14; 21.1.0; 21.1.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-4009
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-4009
Mailing List
https://lists.debian.org/debian-lts-announce/2021/12/msg00035.html
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NKLSZCY47QK4RCJFXITYFALCGPJAFXOK/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NXTRPFEQLFZ6NT2LPLZEID664RGC3OCC/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PDHYZM6FII35JA7J275MFCJO6ADJUPQX/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/T57DCF726O5LLTST4NBL5PQ7DLPB46HT/
Vendor Advisory
https://lists.x.org/archives/xorg-announce/2021-December/003122.html
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