Cisco Alert
3563Warning Date
Severity Level
Warning Number
Target Sector
22 December, 2019
● Critical
2019-751
All
Description:
Cisco has released an alert regarding Self-Signed Certificates (SSC) on the following systems:
- IOS 12.x - All versions
- IOS 15.x - Versions prior to: 15.6(3)M7, 15.7(3)M5, 15.8(3)M3, 15.9(3)M
- IOS-XE - Versions prior to: 16.9.1
Threats:
At 00:00 on 1 January 2020 UTC, all Self-Signed Certificates (SSC) that were generated on IOS/IOS-XE systems will expire. After that time, unfixed IOS systems will be unable to generate new SSCs. Any service that relies on these self-signed certificates might not work.
Best practice and Recommendations:
The CERT team encourages users to update the affected systems:
- Cisco IOS XE Software Release 16.9.1 and later.
- Cisco IOS Software Release 15.6(3)M7 and later; 15.7(3)M5 and later; or 15.8(3)M3 and later.
After you upgrade the software, you must regenerate the self-signed certificate by following one of these methods:
- Obtain a valid certificate from a 3rd part Certificate Authority (CA).
- Use the IOS CA Server to generate a new certificate.
- Use OpenSSL to generate a new self-signed certificate.
For more details:
- https://www.cisco.com/c/en/us/support/docs/security-vpn/public-key-infrastructure-pki/215118-ios-self-signed-certificate-expiration-o.html