Is CVE-2009-3555 being actively exploited?

CVE-2009-3555 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2009-3555?

CVE-2009-3555 has a CVSS 3.1 base score of 9.8 (CRITICAL).

CVE-2009-3555

CRITICAL · CVSS 9.8EPSS 87.3%EU EUVD

The TLS protocol, and the SSL protocol 3.0 and possibly earlier, as used in Microsoft Internet Information Services (IIS) 7.0, mod_ssl in the Apache HTTP Server 2.2.14 and earlier, OpenSSL before 0.9.8l, GnuTLS 2.8.5 and earlier, Mozilla Network Security Services (NSS) 3.12.4 and earlier, multiple Cisco products, and other products, does not properly associate renegotiation handshakes with an existing connection, which allows man-in-the-middle attackers to insert data into HTTPS sessions, and possibly other types of sessions protected by TLS or SSL, by sending an unauthenticated request that is processed retroactively by a server in a post-renegotiation context, related to a "plaintext injection" attack, aka the "Project Mogul" issue.

Key facts

CVSS score: 9.8 (v3.1)
Severity: CRITICAL
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-295
EPSS score: 87.3% (100th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2022-3720)
Published: November 9, 2009
NVD last modified: June 16, 2026
Status: Modified

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2022-3720 in the EU Vulnerability Database. Last updated in EUVD on May 27, 2026.

View on the EU Vulnerability Database

Affected products

apache / http server
canonical / ubuntu linux
canonical / ubuntu linux
canonical / ubuntu linux
canonical / ubuntu linux
canonical / ubuntu linux
canonical / ubuntu linux
debian / debian linux
debian / debian linux
debian / debian linux
debian / debian linux
debian / debian linux
f5 / nginx
fedoraproject / fedora
fedoraproject / fedora
fedoraproject / fedora
fedoraproject / fedora
gnu / gnutls
mozilla / nss
openssl / openssl
openssl / openssl

References

http://archives.neohapsis.com/archives/bugtraq/2013-11/0120.html(Broken Link)
http://blog.g-sec.lu/2009/11/tls-sslv3-renegotiation-vulnerability.html(Third Party Advisory)
http://blogs.iss.net/archive/sslmitmiscsrf.html(Broken Link)
http://blogs.sun.com/security/entry/vulnerability_in_tls_protocol_during(Third Party Advisory)
http://clicky.me/tlsvuln(Exploit, Third Party Advisory)
http://extendedsubset.com/?p=8(Broken Link)
http://extendedsubset.com/Renegotiating_TLS.pdf(Broken Link)
http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=c01945686(Broken Link)
http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=c02436041(Broken Link)
http://itrc.hp.com/service/cki/docDisplay.do?docId=emr_na-c02273751(Broken Link)
http://kbase.redhat.com/faq/docs/DOC-20491(Third Party Advisory)
http://lists.apple.com/archives/security-announce/2010//May/msg00001.html(Mailing List, Third Party Advisory)
http://lists.apple.com/archives/security-announce/2010//May/msg00002.html(Mailing List, Third Party Advisory)
http://lists.apple.com/archives/security-announce/2010/Jan/msg00000.html(Mailing List, Third Party Advisory)
http://lists.fedoraproject.org/pipermail/package-announce/2010-April/039561.html(Third Party Advisory)
http://lists.fedoraproject.org/pipermail/package-announce/2010-April/039957.html(Third Party Advisory)
http://lists.fedoraproject.org/pipermail/package-announce/2010-May/040652.html(Third Party Advisory)
http://lists.fedoraproject.org/pipermail/package-announce/2010-October/049455.html(Third Party Advisory)
http://lists.fedoraproject.org/pipermail/package-announce/2010-October/049528.html(Third Party Advisory)
http://lists.fedoraproject.org/pipermail/package-announce/2010-October/049702.html(Third Party Advisory)
http://lists.gnu.org/archive/html/gnutls-devel/2009-11/msg00029.html(Third Party Advisory)
http://lists.opensuse.org/opensuse-security-announce/2009-11/msg00009.html(Third Party Advisory)
http://lists.opensuse.org/opensuse-security-announce/2010-04/msg00001.html(Third Party Advisory)
http://lists.opensuse.org/opensuse-security-announce/2010-05/msg00001.html(Third Party Advisory)
http://lists.opensuse.org/opensuse-security-announce/2010-05/msg00002.html(Third Party Advisory)
http://lists.opensuse.org/opensuse-security-announce/2010-06/msg00001.html(Third Party Advisory)
http://lists.opensuse.org/opensuse-security-announce/2010-10/msg00006.html(Third Party Advisory)
http://lists.opensuse.org/opensuse-security-announce/2010-12/msg00005.html(Third Party Advisory)
http://lists.opensuse.org/opensuse-security-announce/2010-12/msg00006.html(Third Party Advisory)
http://lists.opensuse.org/opensuse-security-announce/2011-07/msg00013.html(Third Party Advisory)
http://lists.opensuse.org/opensuse-security-announce/2011-07/msg00014.html(Third Party Advisory)
http://marc.info/?l=apache-httpd-announce&m=125755783724966&w=2(Third Party Advisory)
http://marc.info/?l=bugtraq&m=126150535619567&w=2(Third Party Advisory)
http://marc.info/?l=bugtraq&m=127128920008563&w=2(Third Party Advisory)
http://marc.info/?l=bugtraq&m=127419602507642&w=2(Third Party Advisory)
http://marc.info/?l=bugtraq&m=127557596201693&w=2(Third Party Advisory)
http://marc.info/?l=bugtraq&m=130497311408250&w=2(Third Party Advisory)
http://marc.info/?l=bugtraq&m=132077688910227&w=2(Third Party Advisory)
http://marc.info/?l=bugtraq&m=133469267822771&w=2(Third Party Advisory)
http://marc.info/?l=bugtraq&m=134254866602253&w=2(Third Party Advisory)

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

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