Skip to content
Fencer Intel
high 7.5

CVE-2009-4565 json

sendmail before 8.14.4 does not properly handle a '\0' character in a Common Name (CN) field of an X.509 certificate, which (1) allows man-…

published 16y ago modified 4mo ago also EUVD-2009-4531

cvss
7.5
version 2.0, NVD
cisa kev
Not listed
not in CISA's catalog
epss
2.4%
EPSS 2.4% chance of exploitation in 30 days, percentile 84%
public exploits
0
none known

Summary

sendmail before 8.14.4 does not properly handle a '\0' character in a Common Name (CN) field of an X.509 certificate, which (1) allows man-in-the-middle attackers to spoof arbitrary SSL-based SMTP servers via a crafted server certificate issued by a legitimate Certification Authority, and (2) allows remote attackers to bypass intended access restrictions via a crafted client certificate issued by a legitimate Certification Authority, a related issue to CVE-2009-2408.

Patch / fix

  • sendmail Debian 14, Debian 13, Debian 12 8.14.3-9.1

debian advisories DEBIAN-CVE-2009-4565

  • sendmail RHEL 4 8.13.1-6.el4
  • sendmail-cf RHEL 4 8.13.1-6.el4
  • sendmail RHEL 5 8.13.8-8.el5
  • sendmail-cf RHEL 5 8.13.8-8.el5

red hat advisories RHSA-2011:0262RHSA-2010:0237

Is CVE-2009-4565 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2009-4565 updated cvss 4.0

sendmail: incorrect verification of SSL certificate with NUL in name

  • Red Hat Enterprise Linux (v. 5 server) sendmail 8.13.8-8.el5, sendmail-cf 8.13.8-8.el5
    fixed: vendor fix RHSA-2010:0237
  • Red Hat Enterprise Linux AS version 4 sendmail 8.13.1-6.el4, sendmail-cf 8.13.1-6.el4
    fixed: vendor fix RHSA-2011:0262
  • Red Hat Enterprise Linux Desktop (v. 5 client) sendmail 8.13.8-8.el5, sendmail-cf 8.13.8-8.el5
    fixed: vendor fix RHSA-2010:0237
  • Red Hat Enterprise Linux Desktop version 4 sendmail 8.13.1-6.el4, sendmail-cf 8.13.1-6.el4
    fixed: vendor fix RHSA-2011:0262
  • Red Hat Enterprise Linux Desktop Workstation (v. 5 client) sendmail 8.13.8-8.el5, sendmail-cf 8.13.8-8.el5
    fixed: vendor fix RHSA-2010:0237
  • Red Hat Enterprise Linux ES version 4 sendmail 8.13.1-6.el4, sendmail-cf 8.13.1-6.el4 Red Hat Enterprise Linux WS version 4 sendmail 8.13.1-6.el4, sendmail-cf 8.13.1-6.el4
    fixed: vendor fix RHSA-2011:0262

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

2.40% chance of exploitation in the next 30 days, higher than 84% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
NVD 2.0 7.5 AV:N/AC:L/Au:N/C:P/I:P/A:P

Classification

Weakness

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.