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CVE-2023-20198, CVE-2023-20273 - Multiple Vulnerabilities in Cisco IOS XE Software Web UI Feature (Last Updated: 1-Nov-2023)
CVE-2023-20198 KEVPublic exploit Critical · 10.0 EPSS 99.6%
Cisco IOS XE Web UI Privilege Escalation Vulnerability
Cisco · IOS XE Web UI
Summary
Cisco IOS XE Web UI contains a flaw that lets an attacker escalate privileges through the web UI feature after gaining initial access, with the flaw being exploited in observed attacks. An attacker on the network with no prior authentication and no user interaction can abuse this weakness, and the write of an implant to the file system indicates the attacker can then gain root-level control of the device.
Official description · NVD
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.
Priority scorePatchfirst’s 0 to 100 ranking. It adds points for CISA KEV listing, ransomware use, EPSS, threat reports, public exploit code and CVSS. Every CVE page shows the breakdown. Breakdown
86.1 / 100
- Exploited
- Yes, in CISA KEV
- Reports
- 2
- Tactics
- 2/15
How an attack unfolds
Based on MITRE ATT&CKA public catalogue of the techniques attackers use, maintained by MITRE. Patchfirst uses it to describe what attackers do with a vulnerability. mappings. Select a step to see the evidence.Exploitation timelineDated milestones for a CVE: when it was disclosed, when exploit code became public, when exploitation was confirmed, and when threat reports named it.
First seen exploited the day it was disclosed. Public exploit code (Metasploit) was available the same day.
- DisclosedFirst seen exploitedVulnCheck KEV evidenceAdded to CISA KEVEU database agreesPublic exploit codeMetasploitday 0
- Named in a threat reportblog.talosintelligence.com+16 mo
CISA KEV listing is when exploitation was confirmed, not necessarily the first attack.
MITRE ATT&CKA public catalogue of the techniques attackers use, maintained by MITRE. Patchfirst uses it to describe what attackers do with a vulnerability. techniques
2 TechniqueOne specific attacker behaviour in MITRE ATT&CK, such as T1190 “Exploit Public-Facing Application”. IDs with a dot, like T1059.004, are sub-techniques., grouped by TacticThe attacker’s goal at a stage of an attack in MITRE ATT&CK, such as Initial Access or Persistence. Each technique belongs to one or more tactics. in kill-chain order, 1 cited passage 2Initial AccessTA0001
MITRE CTID mapping of the KEV entry · how it is exploited
This vulnerability is exploited through improper access control in the Web User Interface feature of Cisco IOS XE software. Attackers first used this vulnerability to gain initial access by issuing a privilege level 15 command, which allowed them to create a local user account with a password.
PersistenceTA0003
Create Account T1136
MITRE CTID mapping of the KEV entry · primary impact
Lower-confidence links (1)
These come from early or generic mappings, text matching, or contradict this CVE’s details (for example a public-facing technique on a bug that needs a user to open a file). Shown for completeness.
- Exploitation for Privilege EscalationT1068 machine-matched from report text
Detection
0 rules for this CVE · 152 general rules for its techniquesRules for this CVE
0Sigma ruleAn open, vendor-neutral detection rule for log data. Security teams convert Sigma rules into searches for their own SIEM. that reference CVE-2023-20198 directly.CVE-specific rules are not available in this build. Search SigmaHQ ↗
General rules for this CVE’s techniques
These detect the technique in general, not this specific vulnerability.
Exploit Public-Facing ApplicationT1190149 general rules
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- Confluence Exploitation CVE-2019-3398criticaltest
- CVE-2010-5278 Exploitation Attemptcriticaltest
- CVE-2020-0688 Exchange Exploitation via Web Logcriticaltest
- CVE-2020-10148 SolarWinds Orion API Auth Bypasscriticaltest
- CVE-2020-5902 F5 BIG-IP Exploitation Attemptcriticaltest
Create AccountT11363 general rules
Sigma rules © SigmaHQ, Detection Rule License 1.1; linked, not reproduced.
What security researchers reported
Named in 2 threat reports2 reportsCisco TalosCISAFeb 2025 · 1 undated
Reports are matched by finding the exact id CVE-2023-20198 in their text; nobody has reviewed the match. One passage is shown per report, at most 320 characters, linked to the original.
Countering Chinese State-Sponsored Actors Compromise of Networks Worldwide to Feed Global Espionage System
CVE-2023-20273 - Cisco Internetworking Operating System (IOS) XE software web management user interface post-authentication command injection/privilege escalation (commonly chained with CVE-2023-20198 for initial access to achieve code execution as root) [T1068]…
4 passages name itOriginal (opens in a new tab) ↗
Also mentioned in 50 community threat pulses (AlienVault OTX)
Weaker evidencePulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.
- Actively_Exploited_Kev | Oct 29, 202628 Oct 2026
- Actively_Exploited_Kev | Oct 28, 202627 Oct 2026
- Actively_Exploited_Kev | Oct 27, 202626 Oct 2026
- Actively_Exploited_Kev | Oct 24, 202623 Oct 2026
- Actively_Exploited_Kev | Oct 23, 202622 Oct 2026
- Actively_Exploited_Kev | Oct 22, 202621 Oct 2026
- 44 more on OTX