Threat landscape
high

Cisco IOS XR: Mehrere Schwachstellen

WID-SEC-2026-0706 · first 12.03.2026 · updated 12.03.2026 · CVSS 8,8

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What it is about

Cisco Internetwork Operating System (IOS) ist ein Betriebssystem, das für Cisco Geräte wie z. B. Router und Switches eingesetzt wird. Ein Angreifer kann mehrere Schwachstellen in Cisco IOS XR ausnutzen, um seine Privilegien zu erhöhen, um beliebigen Code mit root-rechten auszuführen, und um einen Denial of Service Angriff durchzuführen.

Under what conditions?

The BSI does not name any particular preconditions.

What can happen in the worst case

An attacker could use the vulnerability to

  • seine Privilegien zu erhöhen
  • beliebigen Code mit root-rechten auszuführen
  • einen Denial of Service Angriff durchzuführen

Am I affected?

Affected according to the BSI:

  • Cisco IOS XR
  • Cisco IOS XR <25.2.21
  • Cisco IOS XR <25.4.2
  • Cisco IOS XR <25.2.2
  • Cisco IOS XR <25.3.1

The installed version is usually shown under “Help → About” or in the device’s admin interface.

What helps?

Update to at least:

  • Cisco IOS XR 25.2.21
  • Cisco IOS XR 25.4.2
  • Cisco IOS XR 25.2.2
  • Cisco IOS XR 25.3.1

Is the vulnerability already being exploited?

None of the CVEs is in the CISA catalogue of exploited vulnerabilities. That does not mean there are no attacks, only that none are documented.

Information and sources

CVE: CVE-2026-20046, CVE-2026-20074, CVE-2026-20118, CVE-2026-20040

Source: BSI warning and information service (CERT-Bund); CISA. The assessment of the conditions is my reading of the BSI text; the external pages are in their original language.

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