CVE-2005-3774

CVE-2005-3774 is a medium-severity vulnerability in Cisco Pix with a CVSS 2.0 base score of 5.0. Its EPSS exploit-prediction score of 18% places it in the 97th percentile, indicating an elevated likelihood of exploitation.

Key facts

• Severity: Medium (CVSS 2.0 base score 5.0)
• EPSS exploit prediction: 18% (97th percentile)
• Actively exploited: Not listed in CISA KEV
• Affected product: Cisco Pix
• Published: 2005-11-23
• Last modified: 2026-06-16

Description

Cisco PIX 6.3 and 7.0 allows remote attackers to cause a denial of service (blocked new connections) via spoofed TCP packets that cause the PIX to create embryonic connections that that would not produce a valid connection with the end system, including (1) SYN packets with invalid checksums, which do not result in a RST; or, from an external interface, (2) one byte of "meaningless data," or (3) a TTL that is one less than needed to reach the internal destination.

Frequently asked questions

What is CVE-2005-3774?

Cisco PIX 6.3 and 7.0 allows remote attackers to cause a denial of service (blocked new connections) via spoofed TCP packets that cause the PIX to create embryonic connections that that would not produce a valid connection with the end system, including (1) SYN packets with invalid checksums, which do not result in a RST; or, from an external interface, (2) one byte of "meaningless data," or (3) a TTL that is one less than needed to reach the internal destination.

How severe is CVE-2005-3774?

CVE-2005-3774 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2005-3774 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 18% (97th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2005-3774?

CVE-2005-3774 primarily affects Cisco Pix. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2005-3774?

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

When was CVE-2005-3774 published?

CVE-2005-3774 was published on 2005-11-23 and last updated on 2026-06-16.

References

• http://lists.grok.org.uk/pipermail/full-disclosure/2005-November/038971.html
• http://lists.grok.org.uk/pipermail/full-disclosure/2005-November/038983.html
• http://secunia.com/advisories/17670
• http://securitytracker.com/id?1015256
• http://www.cisco.com/en/US/products/hw/vpndevc/ps2030/products_security_notice09186a0080624a37.html
• http://www.cisco.com/warp/public/707/cisco-response-20051122-pix.shtml
• http://www.kb.cert.org/vuls/id/853540
• http://www.osvdb.org/24140
• http://www.securityfocus.com/archive/1/417458/30/0/threaded
• http://www.securityfocus.com/archive/1/426989/100/0/threaded
• http://www.securityfocus.com/archive/1/426991/100/0/threaded
• http://www.securityfocus.com/archive/1/427041/100/0/threaded
• http://www.securityfocus.com/bid/15525
• http://www.vupen.com/english/advisories/2005/2546
• https://exchange.xforce.ibmcloud.com/vulnerabilities/25077
• https://exchange.xforce.ibmcloud.com/vulnerabilities/25079

Affected products (2)

• cpe:2.3:h:cisco:pix:6.3:*:*:*:*:*:*:*
• cpe:2.3:h:cisco:pix:7.0:*:*:*:*:*:*:*

More vulnerabilities in Cisco Pix

• CVE-2007-2462 — Critical (CVSS 10.0): Unspecified vulnerability in Cisco Adaptive Security Appliance (ASA) and PIX 7.2 before 7.2(2)8, when using Layer 2…
• CVE-2009-1159 — High (CVSS 7.8): Unspecified vulnerability on Cisco Adaptive Security Appliances (ASA) 5500 Series and PIX Security Appliances 7.2…
• CVE-2009-1158 — High (CVSS 7.8): Unspecified vulnerability on Cisco Adaptive Security Appliances (ASA) 5500 Series devices 7.0 before 7.0(8)6, 7.1…
• CVE-2009-1157 — High (CVSS 7.8): Memory leak on Cisco Adaptive Security Appliances (ASA) 5500 Series and PIX Security Appliances 7.0 before 7.0(8)6, 7.1…
• CVE-2009-1155 — High (CVSS 7.8): Cisco Adaptive Security Appliances (ASA) 5500 Series and PIX Security Appliances 7.1(1) through 7.1(2)82, 7.2 before…
• CVE-2008-2732 — High (CVSS 7.8): Multiple unspecified vulnerabilities in the SIP inspection functionality in Cisco PIX and Adaptive Security Appliance…

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