Critical severity · published Feb 10, 2021
CVE-2021-27135
xterm before Patch #366 allows remote attackers to execute arbitrary code or cause a denial of service (segmentation fault) via a crafted UTF-8 combining character sequence
9.8
CVSS
7.8%
EPSS
No
On KEV
Description
xterm before Patch #366 allows remote attackers to execute arbitrary code or cause a denial of service (segmentation fault) via a crafted UTF-8 combining character sequence.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)7.8% · higher than 95% 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 · source: NVD
FE
Fedora · Fedoraproject
33 · source: NVD
XT
Xterm · Invisible-island
before 366 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-27135
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-27135
Mailing List
http://seclists.org/fulldisclosure/2021/May/52
Mailing List
http://www.openwall.com/lists/oss-security/2021/02/10/7
Third Party Advisory
https://access.redhat.com/security/cve/CVE-2021-27135
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=1927559
Issue Tracking
https://bugzilla.suse.com/show_bug.cgi?id=1182091
Patch
https://github.com/ThomasDickey/xterm-snapshots/commit/82ba55b8f994ab30ff561a347b82ea340ba7075c
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