Ios XrOperating system · Cisco
CVE-2025-20138
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedA vulnerability in the CLI of Cisco IOS XR Software could allow an authenticated, local attacker to execute arbitrary commands as root on the underlying operating system of an affected device. This vulnerability is due to insufficient validation of user arguments that are passed to specific CLI commands. An attacker with a low-privileged account could exploit this vulnerability by using crafted commands at the prompt. A successful exploit could allow the attacker to elevate privileges to root and execute arbitrary commands.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceA local privilege escalation vulnerability in Cisco IOS XR CLI allows authenticated low-privileged users to execute arbitrary commands as root due to insufficient validation of user-supplied arguments in specific CLI commands.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data
Ios XrOperating system
< 24.2.21>= 24.3, < 24.4CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Local
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Changed
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify Cisco IOS XR versionExecute 'show version' or 'admin show version' in the CLI and locate the software version string (e.g., 'Version 24.2.1'). Compare this version number against the affected ranges: any version less than 24.2.21, or any version from 24.3.0 up to but not including 24.4.Affected if The installed version falls below 24.2.21 or is between 24.3.0 and 24.3.x (where x is less than 4).
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Confirm low-privileged user accounts existExecute 'show users' or 'admin show users' to list all authenticated users currently logged in. Use 'show running-config | include username' or check the user database to identify accounts with privilege levels below 15 (root/Administrator).Affected if Any non-administrator user account (privilege level < 15) exists in the system who has CLI access.
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Verify CLI access for non-admin usersCheck if the low-privileged accounts have shell/CLI access by reviewing 'show privilege' for specific users or by examining authentication configuration via 'show running-config | include aaa' or 'admin show running-config security'.Affected if Low-privileged users can authenticate to the IOS XR CLI and execute commands.
A user is affected if their Cisco IOS XR version is below 24.2.21 or between 24.3.0 and 24.3.x, AND there are authenticated low-privileged CLI users present in the environment who could trigger the insufficient argument validation flaw.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped24.2.2124.4
Apply the vendor-supplied software update/patch for Cisco IOS XR when available. Restrict CLI access to trusted personnel and monitor for unusual command execution.
Cisco IOS XR 24.2.21 (or later) or 24.4 (or later) depending on current branch
- 1. Identify the current Cisco IOS XR version running on the affected device using 'show version' command
- 2. Determine the appropriate upgrade path based on current version (24.2.x series or 24.3.x series)
- 3. Download the fixed Cisco IOS XR software release (24.2.21 or later for 24.2.x branch; 24.4 or later for 24.3.x branch) from Cisco's software download center
- 4. Verify software image integrity using MD5/SHA256 checksums provided by Cisco
- 5. Schedule a maintenance window as upgrades require device reload
- 6. Back up current configuration using 'admin commit backup' or 'copy running-config startup-config'
- 7. Transfer the new software image to the device using TFTP, FTP, or SCP
- 8. Install the new software package using 'install add source <repository> activate' command sequence
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Ios Xr
Scoped from the published advisory
- Consultation4.0 h
- Implementation3.0 h
- Testing4.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,680.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2025-20138 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2025-20138 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
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