What’s Vulnerable › Vulnerabilities

CVE-1999-0063

• Severity: medium (CVSS 5.0 v2.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 8.2% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 1999-01-11 · updated 2026-06-16

Description

Cisco IOS 12.0 and other versions can be crashed by malicious UDP packets to the syslog port.

Affected products

• Cisco IOS: 11.3aa, 11.3db, 12.0, 12.0(1)w, 12.0(1)xa3, 12.0(1)xb (+6)

References

• https://exchange.xforce.ibmcloud.com/vulnerabilities/CVE-1999-0063
• https://exchange.xforce.ibmcloud.com/vulnerabilities/CVE-1999-0063

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