Background exploitation KEV catalog No authentication

CVE-2018-0156

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

CheckOps priority index

5.1/10 Patch within 7 days

Severity7.5

Probability0.9

Exploitation3/5

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

EPSS · today 9.4% higher than 95.4% of CVEs

CVSS 3.1 7.5 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:

Exploited for 1,706 days 03 Mar 2022

CISA due date 17 Mar 2022 for US federal agencies

Exploitation probability EPSS · FIRST

EPSS probability (%)Percentile among all CVEs

Exploitation signals 3 / 5

KEV catalog (CISA)03 Mar 2022
Exploited in EUVD (ENISA)03 Mar 2022
Used by ransomwareno
EPSS above 10 %9.4%
No account, over the networkyes

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 Smart Install feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to trigger a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to improper validation of packet data. An attacker could exploit this vulnerability by sending a crafted packet to an affected device on TCP port 4786. Only Smart Install client switches are affected. Cisco devices that are configured as a Smart Install director are not affected by this vulnerability. Cisco Bug IDs: CSCvd40673.

Affected products

Cisco IOS and IOS XEIOS Software and Cisco IOS XE Software

Affected versions

Cisco IOS and IOS XE

Weaknesses (CWE)

CWE-399

Open source packages OSV

Affected libraries according to OSV, with fixed versions.

Timeline

28 Mar 2018
Published
03 Mar 2022
Exploitation reported (ENISA)
03 Mar 2022
Added to the KEV catalog
17 Mar 2022
CISA remediation due date

References

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