How severe is CVE-2019-12643?

CVE-2019-12643 has a CVSS 3.x base score of 10.0, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2019-12643 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-12643?

CVE-2019-12643 primarily affects Cisco Ios Xe. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-12643?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2019-12643 published?

CVE-2019-12643 was published on 2019-08-28 and last updated on 2026-06-17.

CVE-2019-12643

CVE-2019-12643 is a critical-severity vulnerability in Cisco Ios Xe with a CVSS 3.x base score of 10.0. 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-287.

Key facts

Severity: Critical (CVSS 3.x base score 10.0)
CVSS v2: 10.0
EPSS exploit prediction: 5% (92nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Cisco Ios Xe
Published: 2019-08-28
Last modified: 2026-06-17

Description

A vulnerability in the Cisco REST API virtual service container for Cisco IOS XE Software could allow an unauthenticated, remote attacker to bypass authentication on the managed Cisco IOS XE device. The vulnerability is due to an improper check performed by the area of code that manages the REST API authentication service. An attacker could exploit this vulnerability by submitting malicious HTTP requests to the targeted device. A successful exploit could allow the attacker to obtain the token-id of an authenticated user. This token-id could be used to bypass authentication and execute privileged actions through the interface of the REST API virtual service container on the affected Cisco IOS XE device. The REST API interface is not enabled by default and must be installed and activated separately on IOS XE devices. See the Details section for more information.

Frequently asked questions

What is CVE-2019-12643?: A vulnerability in the Cisco REST API virtual service container for Cisco IOS XE Software could allow an unauthenticated, remote attacker to bypass authentication on the managed Cisco IOS XE device. The vulnerability is due to an improper check performed by the area of code that manages the REST API authentication service. An attacker could exploit this vulnerability by submitting malicious HTTP requests to the targeted device. A successful exploit could allow the attacker to obtain the token-id of an authenticated user. This token-id could be used to bypass authentication and execute privileged actions through the interface of the REST API virtual service container on the affected Cisco IOS XE device. The REST API interface is not enabled by default and must be installed and activated separately on IOS XE devices. See the Details section for more information.
How severe is CVE-2019-12643?: CVE-2019-12643 has a CVSS 3.x base score of 10.0, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2019-12643 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-12643?: CVE-2019-12643 primarily affects Cisco Ios Xe. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-12643?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2019-12643 published?: CVE-2019-12643 was published on 2019-08-28 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190828-iosxe-rest-auth-bypass

Affected products (2)

cpe:2.3:o:cisco:ios_xe:15.5\(3\)s3.16:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.6.5:*:*:*:*:*:*:*

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