CVE-2017-3827

CVE-2017-3827 is a medium-severity vulnerability in Cisco Web Security Appliance with a CVSS 3.x base score of 5.8. 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

Description

A vulnerability in the Multipurpose Internet Mail Extensions (MIME) scanner of Cisco AsyncOS Software for Cisco Email Security Appliances (ESA) and Web Security Appliances (WSA) could allow an unauthenticated, remote attacker to bypass configured user filters on the device. Affected Products: This vulnerability affects all releases prior to the first fixed release of Cisco AsyncOS Software for Cisco ESA and Cisco WSA, both virtual and hardware appliances, that are configured with message or content filters to scan incoming email attachments on the ESA or services scanning content of web access on the WSA. More Information: SCvb91473, CSCvc76500. Known Affected Releases: 10.0.0-203 9.9.9-894 WSA10.0.0-233.

Frequently asked questions

What is CVE-2017-3827?
A vulnerability in the Multipurpose Internet Mail Extensions (MIME) scanner of Cisco AsyncOS Software for Cisco Email Security Appliances (ESA) and Web Security Appliances (WSA) could allow an unauthenticated, remote attacker to bypass configured user filters on the device. Affected Products: This vulnerability affects all releases prior to the first fixed release of Cisco AsyncOS Software for Cisco ESA and Cisco WSA, both virtual and hardware appliances, that are configured with message or content filters to scan incoming email attachments on the ESA or services scanning content of web access on the WSA. More Information: SCvb91473, CSCvc76500. Known Affected Releases: 10.0.0-203 9.9.9-894 WSA10.0.0-233.
How severe is CVE-2017-3827?
CVE-2017-3827 has a CVSS 3.x base score of 5.8, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2017-3827 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-2017-3827?
CVE-2017-3827 primarily affects Cisco Web Security Appliance. In total, 12 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2017-3827?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2017-3827 published?
CVE-2017-3827 was published on 2017-02-22 and last updated on 2026-06-17.

References

Affected products (12)

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