How severe is CVE-1999-0453?

CVE-1999-0453 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-1999-0453 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-1999-0453?

CVE-1999-0453 affects Cisco Router. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-1999-0453?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-1999-0453 published?

CVE-1999-0453 was published on 1999-01-01 and last updated on 2026-06-16.

CVE-1999-0453

CVE-1999-0453 is a medium-severity vulnerability in Cisco Router with a CVSS 2.0 base score of 5.0. 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-200.

Key facts

Severity: Medium (CVSS 2.0 base score 5.0)
EPSS exploit prediction: 1% (70th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-200
Affected product: Cisco Router
Published: 1999-01-01
Last modified: 2026-06-16

Description

An attacker can identify a CISCO device by sending a SYN packet to port 1999, which is for the Cisco Discovery Protocol (CDP).

Frequently asked questions

What is CVE-1999-0453?: An attacker can identify a CISCO device by sending a SYN packet to port 1999, which is for the Cisco Discovery Protocol (CDP).
How severe is CVE-1999-0453?: CVE-1999-0453 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-1999-0453 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-1999-0453?: CVE-1999-0453 affects Cisco Router. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-1999-0453?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-1999-0453 published?: CVE-1999-0453 was published on 1999-01-01 and last updated on 2026-06-16.

References

https://exchange.xforce.ibmcloud.com/vulnerabilities/CVE-1999-0453

Affected products (1)

cpe:2.3:h:cisco:router:*:*:*:*:*:*:*:*

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