Cisco is providing an update for the ongoing investigation into observed exploitation of the web UI feature in Cisco IOS XE Software.
Affects Cisco IOS XE Software when the web UI is enabled through the ip http server or ip http secure-server commands. Cisco has released free software updates that address the vulnerabilities.
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Listed in CISA KEV
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Actively exploited
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
Cisco IOS XE Software's web UI feature is affected. A remote attacker could exploit these flaws to gain access, create a local user account, escalate that account to root-level control, and install malicious software on the device.
Summarized by anthropic/claude-haiku-5.5. Verify details against the original sources.
Read the original 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.
Timeline
- Added to CISA KEV
CISA has evidence of exploitation in the wild
- CVE published
- CISA remediation deadline
Due date for US federal agencies to patch
- Record last updated
- EPSS reached 10%
FIRST estimates at least a 10% chance of exploitation in the next 30 days
Affected versions
- Cisco Cisco IOS XE Software
16.1.1, 16.1.2, 16.1.3, 16.2.1, 16.2.2, 16.3.1, 16.3.2, 16.3.3, 16.3.1a, 16.3.4, 16.3.5, 16.3.5b, 16.3.6, 16.3.7, 16.3.8, 16.3.9, 16.3.10, 16.3.11, 16.4.1, 16.4.2, 16.4.3, 16.5.1, 16.5.1a, 16.5.1b, 16.5.2, 16.5.3, 16.6.1, 16.6.2, 16.6.3, 16.6.4, and 156 more
References 1
sec.cloudapps.cisco.com
Questions about CVE-2023-20198
What does this mean?
An attacker gains initial access, creates a local user, uses that user to elevate privilege to root, and writes an implant to the file system.Source: sec.cloudapps.cisco.com
Am I affected, and how do I check?
Cisco IOS XE Software is affected when the web UI feature is enabled. The web UI is enabled through the ip http server or ip http secure-server commands, which can be checked with show running-config | include ip http.Source: sec.cloudapps.cisco.com
What should I do about it?
Install the free Cisco IOS XE software update that addresses these vulnerabilities. The fixed release versions are not listed in the checked facts, so confirm them in Cisco's advisory.Source: sec.cloudapps.cisco.com
Is it being exploited?
Yes. CISA added it to its Known Exploited Vulnerabilities catalog on 2023-10-16, which means it has evidence of attacks. No public exploit code is tracked.Source: cisa.gov, cve.now feed data
What if there's no patch?
Disable the HTTP Server feature by running no ip http server or no ip http secure-server.Source: sec.cloudapps.cisco.com
Why do the sources disagree?
The advisory description refers to a local vector, but the CVSS vector lists network access (AV:N). The sources do not agree on how the issue is reached.Source: sec.cloudapps.cisco.com