CVE-2011-1775
CVE-2011-1775 is a medium-severity vulnerability in Tigervnc with a CVSS 2.0 base score of 5.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.
Key facts
- Severity: Medium (CVSS 2.0 base score 5.8)
- EPSS exploit prediction: 1% (67th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-20
- Affected product: Tigervnc
- Published:
- Last modified:
Description
The CSecurityTLS::processMsg function in common/rfb/CSecurityTLS.cxx in the vncviewer component in TigerVNC 1.1beta1 does not properly verify the server's X.509 certificate, which allows man-in-the-middle attackers to spoof a TLS VNC server via an arbitrary certificate.
Frequently asked questions
- What is CVE-2011-1775?
- The CSecurityTLS::processMsg function in common/rfb/CSecurityTLS.cxx in the vncviewer component in TigerVNC 1.1beta1 does not properly verify the server's X.509 certificate, which allows man-in-the-middle attackers to spoof a TLS VNC server via an arbitrary certificate.
- How severe is CVE-2011-1775?
- CVE-2011-1775 has a CVSS 2.0 base score of 5.8, rated medium severity.
- Is CVE-2011-1775 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2011-1775?
- CVE-2011-1775 affects Tigervnc. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2011-1775?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2011-1775 published?
- CVE-2011-1775 was published on 2011-05-26 and last updated on 2026-06-16.
References
- http://lists.fedoraproject.org/pipermail/package-announce/2011-May/060567.html
- http://openwall.com/lists/oss-security/2011/05/06/2
- http://openwall.com/lists/oss-security/2011/05/09/7
- http://secunia.com/advisories/44939
- http://www.mail-archive.com/tigervnc-devel%40lists.sourceforge.net/msg01342.html
- http://www.mail-archive.com/tigervnc-devel%40lists.sourceforge.net/msg01345.html
- http://www.mail-archive.com/tigervnc-devel%40lists.sourceforge.net/msg01347.html
- http://www.redhat.com/support/errata/RHSA-2011-0871.html
- http://www.securityfocus.com/bid/47738
- https://bugzilla.redhat.com/show_bug.cgi?id=702470
- https://bugzilla.redhat.com/show_bug.cgi?id=702672
Affected products (1)
- cpe:2.3:a:tigervnc:tigervnc:1.1:beta1:*:*:*:*:*:*
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