How severe is CVE-2023-20198?

CVE-2023-20198 has a CVSS score of 10/10, rated CRITICAL. Immediate patching is strongly recommended.

Which products are affected by CVE-2023-20198?

CVE-2023-20198 affects the following products: cisco ios xe, rockwellautomation allen-bradley stratix 5200 firmware, rockwellautomation allen-bradley stratix 5800 firmware.

How do I patch CVE-2023-20198?

Apply the cisco ios xe security patch or hotfix for CVE-2023-20198 on the affected version, following the vendor advisory for your exact build.

How do I detect CVE-2023-20198 across my infrastructure?

Inventory every cisco ios xe deployment and check each version against the affected-products list above.

How do I mitigate CVE-2023-20198 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands. Alongside that, restrict the management interface to trusted networks and apply the vendor's recommended configuration mitigations.

Is CVE-2023-20198 actively exploited in the wild?

Yes. There are 33 known exploit references for CVE-2023-20198, including 20 in-the-wild exploitations observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2023-20198?

CVE-2023-20198 has an EPSS (Exploit Prediction Scoring System) score of 99.6%, placing it in the 100th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. A score above 50% indicates significantly elevated exploitation risk — immediate patching is strongly recommended.

Is CVE-2023-20198 in the CISA Known Exploited Vulnerabilities catalog?

Yes. CVE-2023-20198 (Cisco IOS XE Web UI Privilege Escalation Vulnerability) was added to CISA's Known Exploited Vulnerabilities (KEV) catalog on 2023-10-16. CISA required all US federal civilian agencies to remediate this vulnerability by 2023-10-20. The required action was: Verify that instances of Cisco IOS XE Web UI are in compliance with BOD 23-02 and apply mitigations per vendor instructions. For affected products (Cisco IOS XE Web UI exposed to the internet or to untrusted networks), follow vendor instructions to determine if a system may have been compromised and immediately report positive findings to CISA. Being listed in the KEV catalog is the strongest possible confirmation of active exploitation — treat this as a critical priority.

What type of vulnerability is CVE-2023-20198?

CVE-2023-20198 is classified as CWE-420 (CWE-420). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

Which products and versions are affected by CVE-2023-20198?

CVE-2023-20198 affects cisco ios xe; rockwellautomation allen-bradley stratix 5200 firmware; rockwellautomation allen-bradley stratix 5800 firmware. Check the affected-products list on this page against your deployed version to confirm exposure.

Is there exploit tooling available for CVE-2023-20198?

A Nuclei detection template exists for CVE-2023-20198, meaning automated scanners can fingerprint it. Public exploit tooling significantly increases real-world risk — prioritize patching and ensure detection coverage. Exploit tooling should only ever be used in isolated, authorized testing environments.

When was CVE-2023-20198 published, and has it been updated?

CVE-2023-20198 was published on October 16, 2023 and was last updated on June 17, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🛡️

CISA KEV · ACTIVELY EXPLOITED

CRITICAL severity

CVE-2023-20198 — IOS XE

CRITICAL

CVE-2023-20198 is a critical-severity (CVSS 10) CWE-420 vulnerability in cisco ios xe. It is in CISA's Known Exploited Vulnerabilities catalog (added 2023-10-16) — treat it as actively exploited and patch now. A fix is available — see the affected versions and patch details below.

Cisco is providing an update for the ongoing investigation into observed exploitation of the web UI feature in Cisco IOS XE Software. We are updating the list of fixed releases and…

Published

Oct 16, 2023

Updated

Jun 17, 2026

Affected

3 products

Patched

See advisory

Exploits

33 known

Exploitation data as of Oct 26, 2026 · OSV.dev, NVD, CISA KEV, FIRST.org (EPSS)

Exploitation Status

Actively exploited in the wild

Confirmed by CISA's Known Exploited Vulnerabilities catalog on 2023-10-16. Federal agencies were required to remediate by 2023-10-20.
CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
A successful exploit gives an attacker total control of the affected component, not partial access.

Exploitation and automatability from CISA (KEV catalog and SSVC triage) for CVE-2023-20198.

EPSS Exploitation Probability

via FIRST.org ↗

99.6%probability of exploitation in next 30 days

Very High Risk+0.04%

Lower risk than most CVEs100th percentile — riskier than 100% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2023-20198 by exploitation likelihood (EPSS) against impact (CVSS). In the shaded patch-first corner (EPSS 50%+, CVSS 7.0+).

Where this sits among everything scored

Of 395,492 CVEs with a current EPSS score, this one falls in the ≥ 90% band (highlighted). Counts from FIRST.org, log-scaled.

Description

Cisco is providing an update for the ongoing investigation into observed exploitation of the web UI feature in Cisco IOS XE Software. We are updating the list of fixed releases and adding the Software Checker. Our investigation has determined that the actors exploited two previously unknown issues. The attacker first exploited CVE-2023-20198 to gain initial access and issued a privilege 15 command to create a local user and password combination. This allowed the user to log in with normal user access. The attacker then exploited another component of the web UI feature, leveraging the new local user to elevate privilege to root and write the implant to the file system. Cisco has assigned CVE-2023-20273 to this issue. CVE-2023-20198 has been assigned a CVSS Score of 10.0. CVE-2023-20273 has been assigned a CVSS Score of 7.2. Both of these CVEs are being tracked by CSCwh87343.

Affected Products

3 products · 6 configurations

ios xecisco

≥ 17.9 && < 17.9.4a

range

allen-bradley stratix 5200 firmwarerockwellautomation

< 17.12.02

range

allen-bradley stratix 5800 firmwarerockwellautomation

< 17.12.02

range

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.