How severe is CVE-2019-15956?

CVE-2019-15956 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2019-15956 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-15956?

CVE-2019-15956 primarily affects Cisco Asyncos. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-15956?

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-2019-15956 published?

CVE-2019-15956 was published on 2019-11-26 and last updated on 2026-06-17.

CVE-2019-15956

CVE-2019-15956 is a high-severity vulnerability in Cisco Asyncos with a CVSS 3.x base score of 8.8. 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-284.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 1% (61st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-284
Affected product: Cisco Asyncos
Published: 2019-11-26
Last modified: 2026-06-17

Description

A vulnerability in the web management interface of Cisco AsyncOS Software for Cisco Web Security Appliance (WSA) could allow an authenticated, remote attacker to perform an unauthorized system reset on an affected device. The vulnerability is due to improper authorization controls for a specific URL in the web management interface. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. A successful exploit could have a twofold impact: the attacker could either change the administrator password, gaining privileged access, or reset the network configuration details, causing a denial of service (DoS) condition. In both scenarios, manual intervention is required to restore normal operations.

Frequently asked questions

What is CVE-2019-15956?: A vulnerability in the web management interface of Cisco AsyncOS Software for Cisco Web Security Appliance (WSA) could allow an authenticated, remote attacker to perform an unauthorized system reset on an affected device. The vulnerability is due to improper authorization controls for a specific URL in the web management interface. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. A successful exploit could have a twofold impact: the attacker could either change the administrator password, gaining privileged access, or reset the network configuration details, causing a denial of service (DoS) condition. In both scenarios, manual intervention is required to restore normal operations.
How severe is CVE-2019-15956?: CVE-2019-15956 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2019-15956 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-15956?: CVE-2019-15956 primarily affects Cisco Asyncos. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-15956?: 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-2019-15956 published?: CVE-2019-15956 was published on 2019-11-26 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20191106-wsa-unauth-devreset

Affected products (4)

cpe:2.3:o:cisco:asyncos:*:*:*:*:*:*:*:*
cpe:2.3:a:cisco:web_security_appliance:10.5.2-072:*:*:*:*:*:*:*
cpe:2.3:a:cisco:web_security_appliance:11.5.1-fcs-125:*:*:*:*:*:*:*
cpe:2.3:a:cisco:web_security_appliance:11.7.0-fcs-418:*:*:*:*:*:*:*

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