Command InjectionWeakness · CWE-77

CVE-2025-20334

HIGH · 8.8 CVSS v3.1 Published 2025-09-24
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
95/100
Remediation priority · Urgent
Remotely reachable No privileges

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 · unedited
A vulnerability in the HTTP API subsystem of Cisco IOS XE Software could allow a remote attacker to inject commands that will execute with root privileges into the underlying operating system. This vulnerability is due to insufficient input validation. An attacker with administrative privileges could exploit this vulnerability by authenticating to an affected system and performing an API call with crafted input. Alternatively, an unauthenticated attacker could persuade a legitimate user with administrative privileges who is currently logged in to the system to click a crafted link. A successful exploit could allow the attacker to execute arbitrary commands as the root user.

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 confidence

This is a command injection vulnerability in the HTTP API subsystem of Cisco IOS XE Software. The vulnerability stems from insufficient input validation, allowing an attacker with administrative privileges to inject and execute arbitrary OS commands through crafted API calls. An unauthenticated attacker could also exploit this by tricking a logged-in administrator into clicking a malicious link, potentially leveraging session-based attack vectors. Successful exploitation grants root-level command execution on the underlying operating system.

MitigationApply the vendor-supplied patches for Cisco IOS XE Software; until then, restrict HTTP API access to trusted administrative users only and minimize the exposure of privileged admin sessions.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS 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
Network
Complexity
Low
Privileges
None
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/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 checks

Work through these to decide whether this CVE applies to you.

  1. Confirm Cisco IOS XE is running
    Execute 'show version' and look for 'IOS XE' in the output. Note the full version string (e.g., 17.9.4).
    Affected if The device is not running Cisco IOS XE, then it is not affected by this specific CVE.
  2. Check if HTTP server is enabled
    Run 'show running-config | include ip http server|ip http secure-server' or 'show ip http server status'. Also check for 'restApi' in the configuration via 'show running-config | include restApi'.
    Affected if If HTTP server (secure or non-secure) and REST API are both disabled, the attack surface is significantly reduced.
  3. Determine the IOS XE version and compare
    Obtain the exact version from 'show version' output. Consult the Cisco IOS XE version history to identify whether your version falls within the vulnerable release train. Common affected trains include earlier 16.x, 17.x, and some 21.x/22.x releases depending on the advisory timeline.
    Affected if If your installed version is older than the first fixed release and HTTP services are enabled, the system is likely vulnerable.
  4. Verify administrative user access controls
    Review 'show users' and 'show privilege' to see currently active administrative sessions. Check 'show running-config | include username' to list local admin accounts.
    Affected if If multiple admin users have active sessions or if weak administrative accounts exist, the risk of privilege escalation or session hijacking is higher.
  5. Inspect HTTP API logs for suspicious activity
    Run 'show logging | include HTTP' or check syslog/sd-wan logs for API endpoint access patterns. Look for unexpected API calls, especially to endpoints like /api/v1 or /api/tunnel.
    Affected if If logs show anomalous API requests, especially from unexpected sources or at unusual times, this may indicate exploitation attempts.

If the device runs a vulnerable Cisco IOS XE version with HTTP/HTTPS server and REST API enabled, and administrative users have active sessions, the environment is potentially affected by this command injection flaw.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply the vendor-supplied patches for Cisco IOS XE Software; until then, restrict HTTP API access to trusted administrative users only and minimize the exposure of privileged admin sessions.

Have this fixed Scoped from the published advisory
  • Consultation6.0 h
  • Implementation12.0 h
  • Testing6.0 h
  • Review / QA3.0 h
27.0 hours of engineering $4,800
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $7,680.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2025-20334 — 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 sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-20334 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data