Denial of service in Junos OS and Junos OS Evolved BGP implementation

1) Time-of-check Time-of-use (TOCTOU) Race Condition

EUVDB-ID: #VU68369

Risk: Medium

CVSSv3.1: 5.2 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2022-22220

CWE-ID: CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a race condition in Routing Protocol Daemon (rpd) when handling BGP traffic. When a BGP flow route with redirect IP extended community is received, and the reachability to the next-hop of the corresponding redirect IP is flapping, the rpd process might crash.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Juniper Junos OS: 18.4 - 21.1R1-S1

Junos OS Evolved: 20.4 - 21.2-EVO

External links

http://supportportal.juniper.net/s/article/2022-10-Security-Bulletin-Junos-OS-and-Junos-OS-Evolved-Due-to-a-race-condition-the-rpd-process-can-crash-upon-receipt-of-a-BGP-update-message-containing-flow-spec-route-CVE-2022-22220

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.