How severe is CVE-2017-6671?

CVE-2017-6671 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-2017-6671 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-2017-6671?

CVE-2017-6671 primarily affects Cisco Email Security Appliance Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2017-6671?

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-2017-6671 published?

CVE-2017-6671 was published on 2017-06-13 and last updated on 2026-06-17.

CVE-2017-6671

CVE-2017-6671 is a high-severity vulnerability in Cisco Email Security Appliance Firmware 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 Email Security Appliance Firmware
Published: 2017-06-13
Last modified: 2026-06-17

Description

A vulnerability in the email message scanning of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass configured filters on the device, as demonstrated by the Attachment Filter. More Information: CSCvd34632. Known Affected Releases: 10.0.1-087 9.7.1-066. Known Fixed Releases: 10.0.2-020 9.8.1-015.

Frequently asked questions

What is CVE-2017-6671?: A vulnerability in the email message scanning of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass configured filters on the device, as demonstrated by the Attachment Filter. More Information: CSCvd34632. Known Affected Releases: 10.0.1-087 9.7.1-066. Known Fixed Releases: 10.0.2-020 9.8.1-015.
How severe is CVE-2017-6671?: CVE-2017-6671 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-2017-6671 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-2017-6671?: CVE-2017-6671 primarily affects Cisco Email Security Appliance Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2017-6671?: 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-2017-6671 published?: CVE-2017-6671 was published on 2017-06-13 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:cisco:email_security_appliance_firmware:9.7.1-066:*:*:*:*:*:*:*
cpe:2.3:a:cisco:email_security_appliance_firmware:10.0.1-087:*:*:*:*:*:*:*

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