How severe is CVE-2017-6751?

CVE-2017-6751 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2017-6751 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-6751?

CVE-2017-6751 primarily affects Cisco Web Security Appliance. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2017-6751?

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-2017-6751 published?

CVE-2017-6751 was published on 2017-07-25 and last updated on 2026-06-17.

CVE-2017-6751

CVE-2017-6751 is a high-severity vulnerability in Cisco Web Security Appliance with a CVSS 3.x 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 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Web Security Appliance
Published: 2017-07-25
Last modified: 2026-06-17

Description

A vulnerability in the web proxy functionality of the Cisco Web Security Appliance (WSA) could allow an unauthenticated, remote attacker to forward traffic from the web proxy interface of an affected device to the administrative management interface of an affected device, aka an Access Control Bypass Vulnerability. Affected Products: virtual and hardware versions of Cisco Web Security Appliance (WSA). More Information: CSCvd88863. Known Affected Releases: 10.1.0-204 9.0.0-485.

Frequently asked questions

What is CVE-2017-6751?: A vulnerability in the web proxy functionality of the Cisco Web Security Appliance (WSA) could allow an unauthenticated, remote attacker to forward traffic from the web proxy interface of an affected device to the administrative management interface of an affected device, aka an Access Control Bypass Vulnerability. Affected Products: virtual and hardware versions of Cisco Web Security Appliance (WSA). More Information: CSCvd88863. Known Affected Releases: 10.1.0-204 9.0.0-485.
How severe is CVE-2017-6751?: CVE-2017-6751 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2017-6751 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-6751?: CVE-2017-6751 primarily affects Cisco Web Security Appliance. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2017-6751?: 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-2017-6751 published?: CVE-2017-6751 was published on 2017-07-25 and last updated on 2026-06-17.

References

Affected products (10)

cpe:2.3:a:cisco:web_security_appliance:9.0.0-162:*:*:*:*:*:*:*
cpe:2.3:a:cisco:web_security_appliance:9.0.0-193:*:*:*:*:*:*:*
cpe:2.3:a:cisco:web_security_appliance:9.0.0-485:*:*:*:*:*:*:*
cpe:2.3:a:cisco:web_security_appliance:10.0.0-232:*:*:*:*:*:*:*
cpe:2.3:a:cisco:web_security_appliance:10.0.0-233:*:*:*:*:*:*:*
cpe:2.3:a:cisco:web_security_appliance:10.1.0-204:*:*:*:*:*:*:*
cpe:2.3:a:cisco:web_security_virtual_appliance:9.0.0:*:*:*:*:*:*:*
cpe:2.3:a:cisco:web_security_virtual_appliance:10.0.0:*:*:*:*:*:*:*
cpe:2.3:a:cisco:web_security_virtual_appliance:10.1.0:*:*:*:*:*:*:*
cpe:2.3:a:cisco:web_security_virtual_appliance:10.1.1:*:*:*:*:*:*:*

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