CVE-2009-2700

CVE-2009-2700 is a medium-severity vulnerability in Qt with a CVSS 2.0 base score of 4.3. 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 4.3)
• EPSS exploit prediction: 1% (57th percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-20
• Affected product: Qt
• Published: 2009-09-02
• Last modified: 2026-06-16

Description

src/network/ssl/qsslcertificate.cpp in Nokia Trolltech Qt 4.x does not properly handle a '\0' character in a domain name in the Subject Alternative Name field of an X.509 certificate, which allows man-in-the-middle attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority, a related issue to CVE-2009-2408.

Frequently asked questions

What is CVE-2009-2700?

src/network/ssl/qsslcertificate.cpp in Nokia Trolltech Qt 4.x does not properly handle a '\0' character in a domain name in the Subject Alternative Name field of an X.509 certificate, which allows man-in-the-middle attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority, a related issue to CVE-2009-2408.

How severe is CVE-2009-2700?

CVE-2009-2700 has a CVSS 2.0 base score of 4.3, rated medium severity.

Is CVE-2009-2700 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-2700?

CVE-2009-2700 primarily affects Qt. In total, 42 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2009-2700?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2009-2700 published?

CVE-2009-2700 was published on 2009-09-02 and last updated on 2026-06-16.

References

• http://qt.gitorious.org/qt/qt/commit/802d8c02eaa0aa9cd8d0c6cbd18cd814e6337bc6
• http://secunia.com/advisories/36536
• http://secunia.com/advisories/36702
• http://www.mandriva.com/security/advisories?name=MDVSA-2009:225
• http://www.securityfocus.com/bid/36203
• http://www.ubuntu.com/usn/usn-829-1
• http://www.vupen.com/english/advisories/2009/2499

Affected products (42)

• cpe:2.3:a:qt:qt:4.0.0:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.1.0:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.1.1:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.1.2:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.1.3:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.1.4:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.1.5:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.2.0:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.2.1:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.2.3:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.3.0:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.3.1:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.3.2:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.3.3:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.3.4:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.3.5:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.4.0:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.4.1:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.4.2:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.4.3:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.5.0:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.5.1:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.5.2:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.5.3:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.6.0:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.6.0:rc1:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.6.1:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.6.2:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.6.3:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.6.4:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.7.0:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.7.1:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.7.2:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.7.3:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.7.4:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.7.5:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.8.0:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.8.1:*:*:*:*:*:*:*
• cpe:2.3:a:qt:qt:4.8.2:*:*:*:*:*:*:*

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