Cisco IOS, IOS XR, and IOS XE IKEv1 Information Disclosure Vulnerability

CheckOps priority index

8.0/10 Patch within 24 h

Severity7.5

Probability8.8

Exploitation4/5

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

EPSS · today 87.7% higher than 99.8% of CVEs

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

Exploited for 1,264 days 19 May 2023

CISA due date 09 Jun 2023 for US federal agencies

Exploitation probability EPSS · FIRST

EPSS probability (%)Percentile among all CVEs

Exploitation signals 4 / 5

KEV catalog (CISA)19 May 2023
Exploited in EUVD (ENISA)19 May 2023
Used by ransomwareno
EPSS above 10 %87.7%
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

The server IKEv1 implementation in Cisco IOS 12.2 through 12.4 and 15.0 through 15.6, IOS XE through 3.18S, IOS XR 4.3.x and 5.0.x through 5.2.x, and PIX before 7.0 allows remote attackers to obtain sensitive information from device memory via a Security Association (SA) negotiation request, aka Bug IDs CSCvb29204 and CSCvb36055 or BENIGNCERTAIN.

Affected products

IOS, IOS XR, and IOS XE

Weaknesses (CWE)

CWE-200

Open source packages OSV

Affected libraries according to OSV, with fixed versions.

Timeline

19 Sept 2016
Published
19 May 2023
Exploitation reported (ENISA)
19 May 2023
Added to the KEV catalog
09 Jun 2023
CISA remediation due date
26 Sept 2026
EPSS peak: 87.7%

References

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