How severe is CVE-2019-12647?

CVE-2019-12647 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-2019-12647 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-2019-12647?

CVE-2019-12647 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-2019-12647?

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-2019-12647 published?

CVE-2019-12647 was published on 2019-09-25 and last updated on 2026-06-17.

CVE-2019-12647

CVE-2019-12647 is a high-severity vulnerability in Cisco Ios Xe 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-476.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.8
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-476
Affected product: Cisco Ios Xe
Published: 2019-09-25
Last modified: 2026-06-17

Description

A vulnerability in the Ident protocol handler of Cisco IOS and IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability exists because the affected software incorrectly handles memory structures, leading to a NULL pointer dereference. An attacker could exploit this vulnerability by opening a TCP connection to specific ports and sending traffic over that connection. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition.

Frequently asked questions

What is CVE-2019-12647?: A vulnerability in the Ident protocol handler of Cisco IOS and IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability exists because the affected software incorrectly handles memory structures, leading to a NULL pointer dereference. An attacker could exploit this vulnerability by opening a TCP connection to specific ports and sending traffic over that connection. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition.
How severe is CVE-2019-12647?: CVE-2019-12647 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-2019-12647 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-2019-12647?: CVE-2019-12647 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-2019-12647?: 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-2019-12647 published?: CVE-2019-12647 was published on 2019-09-25 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190925-identd-dos

Affected products (2)

cpe:2.3:o:cisco:ios_xe:fuji-16.7.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:fuji-16.8.1:*:*:*:*:*:*:*

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