Back
CVE-2009-3639
The mod_tls module in ProFTPD before 1.3.2b, and 1.3.3 before 1.3.3rc2, when the dNSNameRequired TLS option is enabled, does not properly…
Medium5.8EPSS 5.7%
- Published
- Updated
- Reserved
- Assigned by
- redhat
Description
The mod_tls module in ProFTPD before 1.3.2b, and 1.3.3 before 1.3.3rc2, when the dNSNameRequired TLS option is enabled, does not properly handle a '\0' character in a domain name in the Subject Alternative Name field of an X.509 client certificate, which allows remote attackers to bypass intended client-hostname restrictions via a crafted certificate issued by a legitimate Certification Authority, a related issue to CVE-2009-2408.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 2.0 | Medium5.8 | AV:N/AC:M/Au:N/C:N/I:P/A:P |
- EPSS (exploitation in 30 days)
- 5.7% · top 7.0% of all CVEs (6 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.8.
Weakness
Affected products
n/a
- affected n/a
References (12)
- [oss-security] 20091023 proftpd - mod_tls - Improper SSL/TLS certificate subjectAltName verification (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- FEDORA-2009-11666 (opens in a new tab)vendor-advisoryx_refsource_FEDORAx_transferred
- 37219 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
- FEDORA-2009-11649 (opens in a new tab)vendor-advisoryx_refsource_FEDORAx_transferred
- DSA-1925 (opens in a new tab)vendor-advisoryx_refsource_DEBIANx_transferred
- http://bugs.proftpd.org/show_bug.cgi?id=3275 (opens in a new tab)x_refsource_CONFIRMx_transferred
- [oss-security] 20091023 Re: proftpd - mod_tls - Improper SSL/TLS certificate subjectAltName verification (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- 36804 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
- proftpd-modtls-security-bypass(53936) (opens in a new tab)vdb-entryx_refsource_XFx_transferred
- 37131 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
- MDVSA-2009:288 (opens in a new tab)vendor-advisoryx_refsource_MANDRIVAx_transferred
- https://bugzilla.redhat.com/show_bug.cgi?id=530719 (opens in a new tab)x_refsource_CONFIRMx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2009-3639)Record last updated .