CVE-2006-4339

CVE-2006-4339 is a medium-severity vulnerability in Openssl with a CVSS 2.0 base score of 4.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-310.

Key facts

• Severity: Medium (CVSS 2.0 base score 4.3)
• EPSS exploit prediction: 5% (91st percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-310
• Affected product: Openssl
• Published: 2006-09-05
• Last modified: 2026-06-16

Description

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.

Frequently asked questions

What is CVE-2006-4339?

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.

How severe is CVE-2006-4339?

CVE-2006-4339 has a CVSS 2.0 base score of 4.3, rated medium severity.

Is CVE-2006-4339 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2006-4339?

CVE-2006-4339 primarily affects Openssl. In total, 45 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2006-4339?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2006-4339 published?

CVE-2006-4339 was published on 2006-09-05 and last updated on 2026-06-16.

References

• ftp://patches.sgi.com/support/free/security/advisories/20060901-01-P.asc
• http://dev2dev.bea.com/pub/advisory/238
• http://docs.info.apple.com/article.html?artnum=304829
• http://docs.info.apple.com/article.html?artnum=307177
• http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?lang=en&cc=us&objectID=c01070495
• http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=c01118771
• http://itrc.hp.com/service/cki/docDisplay.do?docId=c00849540
• http://jvn.jp/en/jp/JVN51615542/index.html
• http://jvndb.jvn.jp/ja/contents/2012/JVNDB-2012-000079.html
• http://lists.apple.com/archives/Security-announce/2007/Dec/msg00001.html
• http://lists.apple.com/archives/security-announce/2006/Nov/msg00001.html
• http://lists.vmware.com/pipermail/security-announce/2008/000008.html
• http://marc.info/?l=bind-announce&m=116253119512445&w=2
• http://marc.info/?l=bugtraq&m=130497311408250&w=2
• http://openvpn.net/changelog.html
• http://secunia.com/advisories/21709
• http://secunia.com/advisories/21767
• http://secunia.com/advisories/21776
• http://secunia.com/advisories/21778
• http://secunia.com/advisories/21785
• http://secunia.com/advisories/21791
• http://secunia.com/advisories/21812
• http://secunia.com/advisories/21823
• http://secunia.com/advisories/21846
• http://secunia.com/advisories/21852
• http://secunia.com/advisories/21870
• http://secunia.com/advisories/21873
• http://secunia.com/advisories/21906
• http://secunia.com/advisories/21927
• http://secunia.com/advisories/21930

Affected products (45)

• cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.1c:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.2b:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.3:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.3a:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.4:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.5:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.5:beta1:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.5:beta2:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.5a:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.5a:beta1:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.5a:beta2:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.6:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.6:beta1:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.6:beta2:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.6:beta3:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.6a:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.6a:beta1:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.6a:beta2:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.6a:beta3:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.6b:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.6c:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.6d:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.6e:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.6f:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.6g:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.6h:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.6i:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.6j:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.6k:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.6l:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.6m:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.7a:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.7b:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.7c:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.7d:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.7e:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.7f:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.7g:*:*:*:*:*:*:*
• cpe:2.3:a:openssl:openssl:0.9.7h:*:*:*:*:*:*:*

More vulnerabilities in Openssl

• CVE-2009-3245 — Critical (CVSS 10.0): OpenSSL before 0.9.8m does not check for a NULL return value from bn_wexpand function calls in (1) crypto/bn/bn_div.c,…
• CVE-2006-3738 — Critical (CVSS 10.0): Buffer overflow in the SSL_get_shared_ciphers function in OpenSSL 0.9.7 before 0.9.7l, 0.9.8 before 0.9.8d, and earlier…
• CVE-2026-31789 — Critical (CVSS 9.8): Issue summary: Converting an excessively large OCTET STRING value to a hexadecimal string leads to a heap buffer…
• CVE-2022-2274 — Critical (CVSS 9.8): The OpenSSL 3.0.4 release introduced a serious bug in the RSA implementation for X86_64 CPUs supporting the AVX512IFMA…
• CVE-2021-3711 — Critical (CVSS 9.8): In order to decrypt SM2 encrypted data an application is expected to call the API function EVP_PKEY_decrypt().…
• CVE-2016-6309 — Critical (CVSS 9.8): statem/statem.c in OpenSSL 1.1.0a does not consider memory-block movement after a realloc call, which allows remote…

All CVEs affecting Openssl →

Other CWE-310 (Cryptographic Issues) vulnerabilities

• CVE-2014-7878 — Critical (CVSS 10.0): The Application Lifecycle Service (ALS) in HP Helion Cloud Development Platform 1.0, when a virtual machine is derived…
• CVE-2013-3712 — Critical (CVSS 10.0): SUSE Studio Onsite 1.3.x before 1.3.6 and SUSE Studio Extension for System z 1.3 uses "static" secret tokens, which has…
• CVE-2013-6952 — Critical (CVSS 10.0): The Belkin WeMo Home Automation firmware before 3949 has a hardcoded GPG key, which makes it easier for remote…
• CVE-2013-6838 — Critical (CVSS 10.0): An unspecified Enghouse Interactive Professional Services "addon product" in Enghouse Interactive IVR Pro (VIP2000)…
• CVE-2013-0137 — Critical (CVSS 10.0): The default configuration of the Digital Alert Systems DASDEC EAS device before 2.0-2 and the Monroe Electronics R189…
• CVE-2011-5123 — Critical (CVSS 10.0): The Antivirus component in Comodo Internet Security before 5.3.175888.1227 does not check whether X.509 certificates in…

Browse all CWE-310 (Cryptographic Issues) vulnerabilities →

Threat intelligence

Threat-intel indicators referencing this CVE:

• 90.160.135.217 (ipv4-addr)
• 62.36.19.42 (ipv4-addr)
• 62.36.19.41 (ipv4-addr)