CVE-2006-4339: Openssl: openssl: signature forgery via improper pkcs-1 padding removal leading to certificate validation bypass

Published Sep 5, 2006
·
Updated

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.

Other sources

OpenSSL before 0.9.7, 0.9.7 before 0.9.7k, and 0.9.8 before 0.9.8c, when using an RSA key with exponent 3, removes PKCS-1 padding before generating a hash, which allows remote attackers to forge a PKCS #1 v1.5 signature that is signed by that RSA key and prevents OpenSSL from correctly verifying X.509 and other certificates that use PKCS #1.

Affected Software

49 affected componentsFixes available
OpenSSL OpenSSL=0.9.5a-beta2
OpenSSL OpenSSL=0.9.8b
OpenSSL OpenSSL=0.9.6i
OpenSSL OpenSSL=0.9.3
OpenSSL OpenSSL=0.9.7c
OpenSSL OpenSSL=0.9.5-beta1
OpenSSL OpenSSL=0.9.6d
OpenSSL OpenSSL=0.9.1c
OpenSSL OpenSSL=0.9.6
OpenSSL OpenSSL=0.9.7j
OpenSSL OpenSSL=0.9.6a
OpenSSL OpenSSL<=0.9.7
OpenSSL OpenSSL=0.9.4
OpenSSL OpenSSL=0.9.6a-beta2
OpenSSL OpenSSL=0.9.5a
OpenSSL OpenSSL=0.9.6f
OpenSSL OpenSSL=0.9.6-beta3
OpenSSL OpenSSL=0.9.6l
OpenSSL OpenSSL=0.9.7g
OpenSSL OpenSSL=0.9.6e
OpenSSL OpenSSL=0.9.7d
OpenSSL OpenSSL=0.9.6b
OpenSSL OpenSSL=0.9.7e
OpenSSL OpenSSL=0.9.7b
OpenSSL OpenSSL=0.9.6a-beta1
OpenSSL OpenSSL=0.9.6k
OpenSSL OpenSSL=0.9.8a
OpenSSL OpenSSL=0.9.6g
OpenSSL OpenSSL=0.9.6-beta2
OpenSSL OpenSSL=0.9.3a
OpenSSL OpenSSL=0.9.6h
OpenSSL OpenSSL=0.9.7i
OpenSSL OpenSSL=0.9.7h
OpenSSL OpenSSL=0.9.6j
OpenSSL OpenSSL=0.9.8
OpenSSL OpenSSL=0.9.7a
OpenSSL OpenSSL=0.9.6c
OpenSSL OpenSSL=0.9.6-beta1
OpenSSL OpenSSL=0.9.6m
OpenSSL OpenSSL=0.9.5-beta2
OpenSSL OpenSSL=0.9.2b
OpenSSL OpenSSL=0.9.5
OpenSSL OpenSSL=0.9.5a-beta1
OpenSSL OpenSSL=0.9.6a-beta3
OpenSSL OpenSSL=0.9.7f
debian/openssl
3.0.20-1~deb12u23.0.22-1~deb12u23.5.7-1~deb13u23.5.7-1~deb13u33.6.5-1
debian/openssl<0.9.8b-3
0.9.8b-3
debian/openssl<0.9.8b-3
0.9.8b-3
debian/openssl<0.9.8b-3
0.9.8b-3

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade debian/openssl to a version that resolves this vulnerability.

    Fixed in 3.0.20-1~deb12u2Fixed in 3.0.22-1~deb12u2Fixed in 3.5.7-1~deb13u2Fixed in 3.5.7-1~deb13u3Fixed in 3.6.5-1
  2. Upgrade

    Upgrade debian/openssl to a version that resolves this vulnerability.

    Fixed in 0.9.8b-3
  3. Upgrade

    Upgrade OpenSSL to a version that resolves this vulnerability.

    Fixed in 0.9.7k
  4. Upgrade

    Upgrade OpenSSL to a version that resolves this vulnerability.

    Fixed in 0.9.8c

Event History

Sep 5, 2006
CVE Published
via MITRE·05:00 PM
Data Sourced
via MITRE·05:00 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·05:04 PM
RemedyDescriptionSeverityWeaknessAffected Software
Data Sourced
via OSV·05:04 PM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2006-4339?

CVE-2006-4339 is classified as a high-severity vulnerability due to its potential to allow remote signature forgery.

2

How do I fix CVE-2006-4339?

To fix CVE-2006-4339, upgrade OpenSSL to versions 0.9.7k or later, or 0.9.8c or later.

3

What systems are affected by CVE-2006-4339?

CVE-2006-4339 affects multiple versions of OpenSSL prior to 0.9.8c and includes versions such as 0.9.7 and earlier.

4

What type of attacks can exploit CVE-2006-4339?

CVE-2006-4339 can be exploited to perform remote attacks that allow signature forgery, compromising data integrity.

5

Is there a workaround for CVE-2006-4339?

There are no effective workarounds for CVE-2006-4339; the only recommended solution is to update to a secure version.

Company

Resources

Contact

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