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CVE-2006-4339

Openssl: openssl: signature forgery via improper pkcs-1 padding removal leading to certificate validation bypass

publishedCWE-347

A flaw was found in OpenSSL. When configured to use an RSA key with exponent 3, OpenSSL improperly removes PKCS-1 padding before generating a hash. This allows remote attackers to forge PKCS #1 v1.5 signatures. Consequently, OpenSSL may incorrectly verify X.509 and other certificates, leading to a bypass of trust and authentication mechanisms.

Technical severity9.1 criticalCVSS 3.1 · CNA: redhat
Published2006-09-05Source updated 2026-11-04
Collected2026-11-042 attributed sources

Fixes and workarounds

Workaround

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

Source: CNA: redhat

Affected products and versions

ProductVersionsAuthority
Red Hat Enterprise Linux 3
Red Hat
openssl
https://access.redhat.com/downloads/content/package-browser/ 		≥ 0:0.9.7a-33.18; < * (unaffected, rpm)
Other versions: affected 		CNA: redhat
Red Hat Enterprise Linux 3
Red Hat
openssl096b
https://access.redhat.com/downloads/content/package-browser/ 		≥ 0:0.9.6b-16.43; < * (unaffected, rpm)
Other versions: affected 		CNA: redhat
Red Hat Enterprise Linux 4
Red Hat
openssl
https://access.redhat.com/downloads/content/package-browser/ 		≥ 0:0.9.7a-43.11; < * (unaffected, rpm)
Other versions: affected 		CNA: redhat
Red Hat Enterprise Linux 4
Red Hat
openssl096b
https://access.redhat.com/downloads/content/package-browser/ 		≥ 0:0.9.6b-22.43; < * (unaffected, rpm)
Other versions: affected 		CNA: redhat
Red Hat Network Satellite Server v 4.2
Red Hat
rhn-solaris-bootstrap
https://access.redhat.com/downloads/content/package-browser/ 		≥ 0:5.0.2-3; < * (unaffected, rpm)
Other versions: affected 		CNA: redhat
Red Hat Network Satellite Server v 4.2
Red Hat
rhn_solaris_bootstrap_5_0_2_3
https://access.redhat.com/downloads/content/package-browser/ 		≥ 0:1-0; < * (unaffected, rpm)
Other versions: affected 		CNA: redhat
Red Hat Network Satellite Server v 4.2 (RHEL3)
Red Hat
rhn-solaris-bootstrap
https://access.redhat.com/downloads/content/package-browser/ 		≥ 0:5.0.2-3; < * (unaffected, rpm)
Other versions: affected 		CNA: redhat
Red Hat Network Satellite Server v 4.2 (RHEL3)
Red Hat
rhn_solaris_bootstrap_5_0_2_3
https://access.redhat.com/downloads/content/package-browser/ 		≥ 0:1-0; < * (unaffected, rpm)
Other versions: affected 		CNA: redhat
Red Hat Network Satellite Server v 5.0
Red Hat
rhn-solaris-bootstrap
https://access.redhat.com/downloads/content/package-browser/ 		≥ 0:5.0.2-3; < * (unaffected, rpm)
Other versions: affected 		CNA: redhat
Red Hat Network Satellite Server v 5.0
Red Hat
rhn_solaris_bootstrap_5_0_2_3
https://access.redhat.com/downloads/content/package-browser/ 		≥ 0:1-0; < * (unaffected, rpm)
Other versions: affected 		CNA: redhat
Red Hat Network Satellite Server v 5.1
Red Hat
rhn-solaris-bootstrap
https://access.redhat.com/downloads/content/package-browser/ 		≥ 0:5.1.1-3; < * (unaffected, rpm)
Other versions: affected 		CNA: redhat
Red Hat Network Satellite Server v 5.1
Red Hat
rhn_solaris_bootstrap_5_1_1_3
https://access.redhat.com/downloads/content/package-browser/ 		≥ 0:1-0; < * (unaffected, rpm)
Other versions: affected 		CNA: redhat
Red Hat Enterprise Linux 10
Red Hat
edk2
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Enterprise Linux 10
Red Hat
openssl
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Enterprise Linux 10
Red Hat
shim
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Enterprise Linux 10
Red Hat
shim-unsigned-aarch64
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Enterprise Linux 10
Red Hat
shim-unsigned-x64
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Enterprise Linux 6
Red Hat
openssl
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Enterprise Linux 7
Red Hat
openssl
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Enterprise Linux 7
Red Hat
ovmf
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Enterprise Linux 8
Red Hat
compat-openssl10
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Enterprise Linux 8
Red Hat
edk2
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Enterprise Linux 8
Red Hat
mingw-openssl
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Enterprise Linux 8
Red Hat
openssl
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Enterprise Linux 8
Red Hat
shim
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Enterprise Linux 8
Red Hat
shim-unsigned-x64
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Enterprise Linux 9
Red Hat
compat-openssl11
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Enterprise Linux 9
Red Hat
edk2
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Enterprise Linux 9
Red Hat
openssl
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Enterprise Linux 9
Red Hat
shim
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Enterprise Linux 9
Red Hat
shim-unsigned-aarch64
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Enterprise Linux 9
Red Hat
shim-unsigned-x64
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat JBoss Core Services
Red Hat
openssl
https://access.redhat.com/jbossnetwork/restricted/listSoftware.html 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat OpenShift Container Platform 4
Red Hat
openshift/ose-rhel-coreos-8
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat OpenShift Container Platform 4
Red Hat
openshift/ose-rhel-coreos-9
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat

Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.

CVSS assessments

Version / scoreVectorAuthority
3.1 / 9.1
critical		 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:NCNA: redhat

Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

References

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