Is CVE-2015-6291 being actively exploited?

CVE-2015-6291 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2015-6291?

CVE-2015-6291 has a CVSS 2.0 base score of 7.8 (HIGH).

CVE-2015-6291

HIGH · CVSS 7.8EPSS 1.9%EU EUVD

Cisco AsyncOS before 8.5.7-043, 9.x before 9.1.1-023, and 9.5.x and 9.6.x before 9.6.0-046 on Email Security Appliance (ESA) devices mishandles malformed fields during body-contains, attachment-contains, every-attachment-contains, attachment-binary-contains, dictionary-match, and attachment-dictionary-match filtering, which allows remote attackers to cause a denial of service (memory consumption) via a crafted attachment in an e-mail message, aka Bug ID CSCuv47151.

Key facts

CVSS score: 7.8 (v2.0)
Severity: HIGH
CVSS vector: AV:N/AC:L/Au:N/C:N/I:N/A:C
Weakness (CWE): CWE-20
EPSS score: 1.9% (80th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2015-6233)
Published: November 6, 2015
NVD last modified: June 17, 2026
Status: Modified

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2015-6233 in the EU Vulnerability Database. Last updated in EUVD on August 6, 2024.

View on the EU Vulnerability Database

Affected products

cisco / email security appliance
cisco / email security appliance
cisco / email security appliance
cisco / email security appliance
cisco / email security appliance
cisco / email security appliance
cisco / email security appliance
cisco / email security appliance
cisco / email security appliance
cisco / email security appliance
cisco / email security appliance
cisco / email security appliance
cisco / email security appliance
cisco / email security appliance
cisco / email security appliance
cisco / email security appliance

Certified products that may be affected

1 FIPS 140 or Common Criteria certified product, from automated matching by sec-certs.org.

Cisco Email Security Appliance v9.1 - Cisco Systems, Inc. - Common Criteria CCEVS-VR-VID-10631-2015 - archived

References

Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

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