CVE-2026-20074General(cisco / ios_xr)

LOWCVSS 7.4 · HIGH

Signal is active with 1 mentions in latest observed window

Immediate actions

Track advisory updates for patch or workaround availability

Recommended action window: Monitor and triage in normal cycle

NVD description

A vulnerability in the Intermediate System-to-Intermediate System (IS-IS) multi-instance routing feature of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause the IS-IS process to restart unexpectedly. This vulnerability is due to insufficient input validation of ingress IS-IS packets. An attacker could exploit this vulnerability by sending crafted IS-IS packets to an affected device after forming an adjacency. A successful exploit could allow the attacker to cause the IS-IS process to restart unexpectedly, resulting in a temporary loss of connectivity to advertised networks and a denial of service (DoS) condition. Note: The IS-IS protocol is a routing protocol. To exploit this vulnerability, an attacker must be Layer 2-adjacent to the affected device and must have formed an adjacency.  

cisco CVEs Back to dashboard

0.0/ 10 priority

Sources & remediation

Vendor / third-party advisories

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-isis-dos-kDMxpSzK

Weakness type (CWE)

CWE-1287

Priority

LOW

Exploitation

NONE

PoC

NONE

Patch

NONE

Momentum

STABLE

Are you affected?

If you run products in this scope, you should treat this CVE as relevant to your environment.

ios_xr

Threat summary

4 mentions across 3 observed days
Momentum state: stable

What's happening

Technical details provided in 1 signal
General: 2 classified signals
Disclosure: 2 classified signals
Peaked 1d ago at 2 mentions (2026-03-13); latest day: 1
4 total mentions across 3 days

Affected systems

Vendors

cisco

Products

ios_xr

1 version affected across 1 product

Deep dive

Activity timeline4 mentions / 3d

Signal classification2 categories

General

250.0%

Disclosure

250.0%

Referenced assets4 URLs

By indicator

Classification over time

Date	Total	Labels

2026-03-12	1	General1
2026-03-13	2	Disclosure2
2026-03-18	1	General1

Full discourse4 posts

CERT-PY@CERTpy204d
General
⚠️ Vulnerabilidades en productos Cisco ❗ CVE-2026-20074 ❗ CVE-2026-20046 ❗ CVE-2026-20040 ➡️ Más info: https://www.cert.gov.py/vulnerabilidades-en-productos-cisco-11/ https://t.co/dWJ8IQdthG
Post summary
The tweet lists three Cisco CVEs and directs readers to external CERT links for further information, but it provides no details on exploitation, patches, or technical specifics.
01010160
6.6K followersView on X
Infoflowcloud@infoflowcloud209d
Disclosure
🚨*CVE* CVE-2026-20074 A vulnerability in the Intermediate System-to-Intermediate System (IS-IS) multi-instance routing feature of Cisco IOS XR Software could allow an unauthenticated, adja… https://www.cve.org/CVERecord?id=CVE-2026-20074 ----- Traducción: CVE-2026-20074 Una… http://infoflow.cloud`
Post summary
The tweet announces CVE‑2026‑20074, highlighting an unauthenticated vulnerability in Cisco IOS XR’s IS‑IS multi‑instance routing, but offers no PoC, exploit details, or patch information.
0000047
57 followersView on X
CVE@CVEnew209d
Disclosure
CVE-2026-20074 A vulnerability in the Intermediate System-to-Intermediate System (IS-IS) multi-instance routing feature of Cisco IOS XR Software could allow an unauthenticated, adja… https://www.cve.org/CVERecord?id=CVE-2026-20074
Post summary
The text is a short excerpt from the official CVE record for CVE-2026-20074, providing minimal information about a vulnerability in Cisco IOS XR but no evidence of exploitation or remediation.
00000326
56.7K followersView on X
RedPacket Security@RedPacketSec210d
General
CVE Alert: CVE-2026-20074 - Cisco - Cisco IOS XR Software - https://www.redpacketsecurity.com/cve-alert-cve-2026-20074-cisco-cisco-ios-xr-software/ #OSINT #ThreatIntel #CyberSecurity #cve-2026-20074 #cisco #cisco-ios-xr-software
Post summary
The post announces CVE-2026-20074 for Cisco IOS XR Software and includes a link for additional information, but no exploit details, patches, or active exploitation evidence are provided.
0000080
3.5K followersView on X

CPE platform detail2 entries

Part:

Vendor:

Product:

Version:

Target SW:

Target HW:

2 of 2 entries

Part	Vendor	Product	Version	Target SW	Target HW
OS	cisco	ios_xr	-	-	-
OS	cisco	ios_xr	25.3.0	-	-

Explore more

Back to dashboard cisco CVEs ios_xr vulnerabilities

What researchers are saying

CVE-2026-20074

CERT-PY@CERTpyGeneral

The tweet lists three Cisco CVEs and directs readers to external CERT links for further information, but it provides no details on exploitation, patches, or technical specifics.

Infoflowcloud@infoflowcloudDisclosure

The tweet announces CVE‑2026‑20074, highlighting an unauthenticated vulnerability in Cisco IOS XR’s IS‑IS multi‑instance routing, but offers no PoC, exploit details, or patch information.

CVE@CVEnewDisclosure

The text is a short excerpt from the official CVE record for CVE-2026-20074, providing minimal information about a vulnerability in Cisco IOS XR but no evidence of exploitation or remediation.

RedPacket Security@RedPacketSecGeneral

The post announces CVE-2026-20074 for Cisco IOS XR Software and includes a link for additional information, but no exploit details, patches, or active exploitation evidence are provided.