CVE-2009-3291

CVE-2009-3291 is a high-severity vulnerability in Php with a CVSS 2.0 base score of 7.5. 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-20.

Key facts

• Severity: High (CVSS 2.0 base score 7.5)
• EPSS exploit prediction: 3% (85th percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-20
• Affected product: Php
• Published: 2009-09-22
• Last modified: 2026-06-16

Description

The php_openssl_apply_verification_policy function in PHP before 5.2.11 does not properly perform certificate validation, which has unknown impact and attack vectors, probably related to an ability to spoof certificates.

Frequently asked questions

What is CVE-2009-3291?

The php_openssl_apply_verification_policy function in PHP before 5.2.11 does not properly perform certificate validation, which has unknown impact and attack vectors, probably related to an ability to spoof certificates.

How severe is CVE-2009-3291?

CVE-2009-3291 has a CVSS 2.0 base score of 7.5, rated high severity.

Is CVE-2009-3291 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-3291?

CVE-2009-3291 primarily affects Php. In total, 112 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2009-3291?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2009-3291 published?

CVE-2009-3291 was published on 2009-09-22 and last updated on 2026-06-16.

References

• http://lists.apple.com/archives/security-announce/2009/Nov/msg00000.html
• http://lists.opensuse.org/opensuse-security-announce/2009-10/msg00004.html
• http://marc.info/?l=bugtraq&m=127680701405735&w=2
• http://marc.info/?l=bugtraq&m=130497311408250&w=2
• http://secunia.com/advisories/36791
• http://secunia.com/advisories/37482
• http://secunia.com/advisories/40262
• http://support.apple.com/kb/HT3937
• http://www.debian.org/security/2009/dsa-1940
• http://www.osvdb.org/58185
• http://www.php.net/ChangeLog-5.php#5.2.11
• http://www.php.net/releases/5_2_11.php
• http://www.securitytracker.com/id?1022914
• http://www.vupen.com/english/advisories/2009/3184
• https://exchange.xforce.ibmcloud.com/vulnerabilities/53334
• https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A10438
• https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A7394

Affected products (112)

• cpe:2.3:a:php:php:*:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:1.0:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:2.0:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:2.0b10:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:3.0:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:3.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:3.0.2:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:3.0.3:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:3.0.4:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:3.0.5:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:3.0.6:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:3.0.7:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:3.0.8:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:3.0.9:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:3.0.10:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:3.0.11:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:3.0.12:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:3.0.13:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:3.0.14:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:3.0.15:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:3.0.16:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:3.0.17:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:3.0.18:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:4:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:4.0:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:4.0:beta_4_patch1:*:*:*:*:*:*
• cpe:2.3:a:php:php:4.0:beta1:*:*:*:*:*:*
• cpe:2.3:a:php:php:4.0:beta2:*:*:*:*:*:*
• cpe:2.3:a:php:php:4.0:beta3:*:*:*:*:*:*
• cpe:2.3:a:php:php:4.0:beta4:*:*:*:*:*:*
• cpe:2.3:a:php:php:4.0:rc1:*:*:*:*:*:*
• cpe:2.3:a:php:php:4.0:rc2:*:*:*:*:*:*
• cpe:2.3:a:php:php:4.0.0:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:4.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:4.0.1:patch1:*:*:*:*:*:*
• cpe:2.3:a:php:php:4.0.1:patch2:*:*:*:*:*:*
• cpe:2.3:a:php:php:4.0.2:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:4.0.3:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:4.0.3:patch1:*:*:*:*:*:*
• cpe:2.3:a:php:php:4.0.4:*:*:*:*:*:*:*

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Threat intelligence

Threat-intel indicators referencing this CVE:

• 82.199.197.245 (ipv4-addr)
• 58.221.244.34 (ipv4-addr)
• 222.99.52.202 (ipv4-addr)
• 90.160.135.217 (ipv4-addr)
• 76.133.97.153 (ipv4-addr)
• 223.82.97.51 (ipv4-addr)
• 183.6.115.88 (ipv4-addr)
• 62.36.19.42 (ipv4-addr)