Is CVE-2009-4831 being actively exploited?

CVE-2009-4831 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2009-4831?

CVE-2009-4831 has a CVSS 2.0 base score of 5.8 (MEDIUM).

CVE-2009-4831

MEDIUM · CVSS 5.8EPSS 1.4%EU EUVD

Cerulean Studios Trillian 3.1 Basic does not check SSL certificates during MSN authentication, which allows remote attackers to obtain MSN credentials via a man-in-the-middle attack with a spoofed SSL certificate.

Key facts

CVSS score: 5.8 (v2.0)
Severity: MEDIUM
CVSS vector: AV:N/AC:M/Au:N/C:P/I:P/A:N
Weakness (CWE): CWE-295
EPSS score: 1.4% (72th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2009-4794)
Published: April 29, 2010
NVD last modified: June 16, 2026
Status: Modified

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2009-4794 in the EU Vulnerability Database. Last updated in EUVD on August 7, 2024.

View on the EU Vulnerability Database

Affected products

cerulean studios / trillian

References

http://secunia.com/advisories/35620(Broken Link)
http://www.securityfocus.com/archive/1/504573/100/0/threaded(Broken Link, Third Party Advisory, VDB Entry)
http://www.securityfocus.com/bid/35509(Broken Link, Third Party Advisory, VDB Entry)
https://exchange.xforce.ibmcloud.com/vulnerabilities/51400(Third Party Advisory, VDB Entry)

Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

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