CVE-2020-24355

Public Exploit

Description

Zyxel VMG5313-B30B router on firmware 5.13(ABCJ.6)b3_1127, and possibly older versions of firmware are affected by insecure permissions which allows regular and other users to create new users with elevated privileges. This is done by changing "FirstIndex" field in JSON that is POST-ed during account creation. Similar may also be possible with account deletion.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.37%
Vendor Advisory zyxel.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://www.zyxel.com/support/security_advisories.shtml vendor advisory
https://blog.somegeneric.ninja/Zyxel_VMG5153_B30B third party advisory exploit
https://blog.somegeneric.ninja/Zyxel_VMG5153_B30B_part2 third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2020-24355?
CVE-2020-24355 has been scored as a critical severity vulnerability.
How to fix CVE-2020-24355?
To fix CVE-2020-24355, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-24355 being actively exploited in the wild?
It is possible that CVE-2020-24355 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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