Cisco IOS Software and Cisco IOS XE Software Denial-of-Service Vulnerability

CheckOps priority index

3.9/10 Patch within 7 days

Severity6.5

Probability0.2

Exploitation2/5

Severity = CVSS. Probability = EPSS (FIRST). Exploitation = public signals: KEV, EUVD, ransomware, EPSS above 10 %, no account required.

EPSS · today 2.1% higher than 81.8% of CVEs

CVSS 3.1 6.5 AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:

Exploited for 1,706 days 03 Mar 2022

CISA due date 24 Mar 2022 for US federal agencies

Exploitation probability EPSS · FIRST

EPSS probability (%)Percentile among all CVEs

Exploitation signals 2 / 5

KEV catalog (CISA)03 Mar 2022
Exploited in EUVD (ENISA)03 Mar 2022
Used by ransomwareno
EPSS above 10 %2.1%
No account, over the networkno

What to do

Fix

Apply the vendor’s fix as soon as it is available.

CISA guidance: Apply updates per vendor instructions.

Meanwhile

Take the service off the internet or restrict access to it, watch the logs and look for signs of compromise.

Manufacturers (CRA)

Exploited vulnerability in your product: early warning to ENISA within 24 h, then notification within 72 h (Article 14 of the Cyber Resilience Act). The CRA explained

Description ENISA EUVD

A vulnerability in the Autonomic Networking feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause autonomic nodes of an affected system to reload, resulting in a denial of service (DoS) condition. More Information: CSCvd88936. Known Affected Releases: Denali-16.2.1 Denali-16.3.1.

Affected products

Cisco IOS and IOS XEIOS and IOS XE Software

Affected versions

Cisco IOS and IOS XE

Open source packages OSV

Affected libraries according to OSV, with fixed versions.

Timeline

07 Aug 2017
Published
03 Mar 2022
Exploitation reported (ENISA)
03 Mar 2022
Added to the KEV catalog
24 Mar 2022
CISA remediation due date

References

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