High severity · published Sep 27, 2020
CVE-2020-26117
In rfb/CSecurityTLS.cxx and rfb/CSecurityTLS.java in TigerVNC before 1.11.0, viewers mishandle TLS certificate exceptions
8.1
CVSS
3.1%
EPSS
No
On KEV
Description
In rfb/CSecurityTLS.cxx and rfb/CSecurityTLS.java in TigerVNC before 1.11.0, viewers mishandle TLS certificate exceptions. They store the certificates as authorities, meaning that the owner of a certificate could impersonate any server after a client had added an exception.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)3.1% · higher than 88% 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
LE
Leap · Opensuse
15.2 · source: NVD
TI
Tigervnc · Tigervnc
before 1.11.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-26117
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-26117
Broken Link
http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00025.html
Broken Link
http://lists.opensuse.org/opensuse-security-announce/2020-11/msg00024.html
Issue Tracking
https://bugzilla.opensuse.org/show_bug.cgi?id=1176733
Patch
https://github.com/TigerVNC/tigervnc/commit/20dea801e747318525a5859fe4f37c52b05310cb
Patch
https://github.com/TigerVNC/tigervnc/commit/7399eab79a4365434d26494fa1628ce1eb91562b
Patch
https://github.com/TigerVNC/tigervnc/commit/b30f10c681ec87720cff85d490f67098568a9cba
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