Vulnerability · Published Aug 25, 2021 · Assigned by cisco

CVE-2021-1590Cisco NX-OS Software system login block-for Denial of Service Vulnerability

Medium 5.3

In plain English

A medium-severity out-of-bounds write in Cisco NX-OS Software from Cisco. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.4% (higher than 72% of all known vulnerabilities).

Severity (CVSS 3.1)5.3Medium

Exploit odds (30 days)1.4%top 28.3% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

A vulnerability in the implementation of the system login block-for command for Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause a login process to unexpectedly restart, causing a denial of service (DoS) condition. This vulnerability is due to a logic error in the implementation of the system login block-for command when an attack is detected and acted upon. An attacker could exploit this vulnerability by performing a brute-force login attack on an affected device. A successful exploit could allow the attacker to cause a login process to reload, which could result in a delay during authentication to the affected device.

Affected products (as reported)

Vendor	Product	Versions
Cisco	Cisco NX-OS Software	n/a

Weakness: CWE-787 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

References

20210825 Cisco NX-OS Software system login block-for Denial of Service Vulnerability vendor-advisory, x_refsource_CISCO