Critical severity · published Feb 9, 2021
CVE-2021-26937
encoding.c in GNU Screen through 4.8.0 allows remote attackers to cause a denial of service (invalid write access and application crash) or possibly have unspecified other impact…
9.8
CVSS
9.1%
EPSS
No
On KEV
Description
encoding.c in GNU Screen through 4.8.0 allows remote attackers to cause a denial of service (invalid write access and application crash) or possibly have unspecified other impact via a crafted UTF-8 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)9.1% · 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; 10.0 · source: NVD
FE
Fedora · Fedoraproject
32; 33 · source: NVD
SC
Screen · Gnu
through 4.8.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-26937
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-26937
Exploit
http://www.openwall.com/lists/oss-security/2021/02/09/8
Product
https://ftp.gnu.org/gnu/screen/
Mailing List
https://lists.debian.org/debian-lts-announce/2021/02/msg00031.html
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GNWBOIDEPOEQS5RMQVMFKHKXJCGNYWBL/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JJWLXP45POUUYBJRRWPVAWNZDJTLYWVM/
Exploit
https://lists.gnu.org/archive/html/screen-devel/2021-02/msg00000.html
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