Vulnerability · Published Sep 27, 2020 · Assigned by mitre

CVE-2020-26117

High 8.1

In plain English

A high-severity security flaw in the tigervnc package (Debian). There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 3.1% (higher than 88% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS NVD)8.1High

Exploit odds (30 days)3.1%top 12.3% of all CVEs

Exploited in the wildNo reportsnot in CISA KEV

Attack toolingNoneno public tooling known

Official 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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Debian:12	tigervnc	1.10.1+dfsg-9	DEBIAN-CVE-2020-26117
Debian:13	tigervnc	1.10.1+dfsg-9	DEBIAN-CVE-2020-26117
Debian:14	tigervnc	1.10.1+dfsg-9	DEBIAN-CVE-2020-26117
Rocky Linux:8	tigervnc	0:1.11.0-6.el8	RLSA-2021:1783

Affected products (as reported)

Vendor	Product	Versions
n/a	n/a	n/a

References

https://github.com/TigerVNC/tigervnc/releases/tag/v1.11.0 x_refsource_MISC
https://github.com/TigerVNC/tigervnc/commit/f029745f63ac7d22fb91639b2cb5b3ab56134d6e x_refsource_MISC
https://github.com/TigerVNC/tigervnc/commit/b30f10c681ec87720cff85d490f67098568a9cba x_refsource_MISC
https://github.com/TigerVNC/tigervnc/commit/20dea801e747318525a5859fe4f37c52b05310cb x_refsource_MISC
https://github.com/TigerVNC/tigervnc/commit/7399eab79a4365434d26494fa1628ce1eb91562b x_refsource_MISC
https://bugzilla.opensuse.org/show_bug.cgi?id=1176733 x_refsource_MISC
[debian-lts-announce] 20201006 [SECURITY] [DLA 2396-1] tigervnc security update mailing-list, x_refsource_MLIST
openSUSE-SU-2020:1666 vendor-advisory, x_refsource_SUSE
openSUSE-SU-2020:1841 vendor-advisory, x_refsource_SUSE