CVE Watchtower

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CVE-2026-20040NVD

Vulnerability Summary

A 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 on the underlying operating system.
Severity Level
HIGH(8.8)
Published Date
Mar 11, 2026
Last Modified
Jul 1, 2026
Exploitation Status
No confirmed exploitation yet
EPSS Score (30-Day)
0.17%Probability
Root Weakness (CWE)
The software constructs all or part of an OS command using externally-influenced input, but does not properly neutralize special elements.
CVSS v3.1 Base Metrics — Score 8.8 (HIGH)
Attack VectorLocal
Attack ComplexityLow
Privileges RequiredLow
User InteractionNone
ScopeChanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh

Affected & Patched Versions

Affected Versions
  • Cisco Ios Xr < 25.2.21
  • Cisco Ios Xr >= 25.3.1 and < 25.4.2
Patched Versions
  • Cisco Ios Xr 25.2.21
  • Cisco Ios Xr 25.4.2
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🎁7-Day Free Trial — Try Pro or Team, no card required.
📧Email Delivery — Threat intel straight to your inbox.
♾️Unlimited Vendors — Track your entire stack.
🚨All New CVEs — Be the first to know.
📈EPSS Spike Alerts — Catch rising risk before it peaks.
🎯Custom EPSS/CVSS — Filter noise, focus on risk.
🛡️Exploit Intel — A 2nd confirmed-exploit signal beyond KEV.
🐙GitHub Issues — Auto-tracked, no duplicates.
📬Weekly Digest — One clean summary, not inbox spam.
🏷️Watchlist Groups — Tag alerts by team (Infra/AppSec/SOC).
💬Webhooks — Slack & Teams integration.
🔀Smart Routing — Critical alerts to one channel, rest to another.
🚫Ad-Free — Uninterrupted experience.