Arista EOS up to 4.37.0F Rip Agent redirect

Summaryinfo

A vulnerability was found in Arista EOS up to 4.37.0F. It has been rated as problematic. This affects an unknown part of the component Rip Agent. This manipulation causes redirect. This vulnerability appears as CVE-2026-121367. The attack may be initiated remotely. There is no available exploit. Upgrading the affected component is advised.

Detailsinfo

A vulnerability has been found in Arista EOS up to 4.37.0F and classified as problematic. Affected by this vulnerability is an unknown function of the component Rip Agent. The manipulation with an unknown input leads to a redirect vulnerability. The CWE definition for the vulnerability is CWE-601. The web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a redirect. As an impact it is known to affect integrity. The summary by CVE is:

On affected Arista EOS platforms with Routing Information Protocol version 2 (RIPv2) configured, under certain conditions, RIPv2 might be silently enabled on management interfaces even when the RIP agent intends to disable it. It allows an unauthenticated attacker with access to the adjacent network to send crafted RIPv2 route advertisements to the device's management IP address. The device could accept and install those routes without authentication. Successful exploitation could allow the attacker to redirect traffic flows to an attacker-controlled destination, install more-specific routes that blackhole legitimate traffic, or otherwise disrupt network reachability for systems whose traffic passes through the affected device.

It is possible to read the advisory at arista.com. This vulnerability is known as CVE-2026-121367 since 11/03/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1204.001 according to MITRE ATT&CK.

Upgrading to version 4.33.0F eliminates this vulnerability.

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Productinfo

Vendor

• Arista

Name

• EOS

Version

• 4.0
• 4.1
• 4.2
• 4.3
• 4.4
• 4.5
• 4.6
• 4.7
• 4.8
• 4.9
• 4.10
• 4.11
• 4.12
• 4.13
• 4.14
• 4.15
• 4.16
• 4.17
• 4.18
• 4.19
• 4.20
• 4.21
• 4.22
• 4.23
• 4.24
• 4.25
• 4.26
• 4.27
• 4.28
• 4.29
• 4.30
• 4.31
• 4.32
• 4.33.10M
• 4.34.8M
• 4.35.6M
• 4.36.2F
• 4.37.0F

License

• commercial

CPE 2.3info

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CPE 2.2info

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