How severe is CVE-2019-15961?

CVE-2019-15961 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 none, and availability high.

Is CVE-2019-15961 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-15961?

CVE-2019-15961 primarily affects Cisco Email Security Appliance Firmware. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-15961?

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-2019-15961 published?

CVE-2019-15961 was published on 2020-01-15 and last updated on 2026-06-17.

CVE-2019-15961

CVE-2019-15961 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-400.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.1
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-400
Affected product: Cisco Email Security Appliance Firmware
Published: 2020-01-15
Last modified: 2026-06-17

Description

A vulnerability in the email parsing module Clam AntiVirus (ClamAV) Software versions 0.102.0, 0.101.4 and prior could allow an unauthenticated, remote attacker to cause a denial of service condition on an affected device. The vulnerability is due to inefficient MIME parsing routines that result in extremely long scan times of specially formatted email files. An attacker could exploit this vulnerability by sending a crafted email file to an affected device. An exploit could allow the attacker to cause the ClamAV scanning process to scan the crafted email file indefinitely, resulting in a denial of service condition.

Frequently asked questions

What is CVE-2019-15961?: A vulnerability in the email parsing module Clam AntiVirus (ClamAV) Software versions 0.102.0, 0.101.4 and prior could allow an unauthenticated, remote attacker to cause a denial of service condition on an affected device. The vulnerability is due to inefficient MIME parsing routines that result in extremely long scan times of specially formatted email files. An attacker could exploit this vulnerability by sending a crafted email file to an affected device. An exploit could allow the attacker to cause the ClamAV scanning process to scan the crafted email file indefinitely, resulting in a denial of service condition.
How severe is CVE-2019-15961?: CVE-2019-15961 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 none, and availability high.
Is CVE-2019-15961 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-15961?: CVE-2019-15961 primarily affects Cisco Email Security Appliance Firmware. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-15961?: 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-2019-15961 published?: CVE-2019-15961 was published on 2020-01-15 and last updated on 2026-06-17.

References

Affected products (7)

cpe:2.3:a:clamav:clamav:*:*:*:*:*:*:*:*
cpe:2.3:a:clamav:clamav:0.102.0:*:*:*:*:*:*:*
cpe:2.3:o:cisco:email_security_appliance_firmware:11.1.1-042:*:*:*:*:*:*:*
cpe:2.3:o:cisco:email_security_appliance_firmware:11.1.2-023:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:-:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:esm:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*

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