CVE-2022-26531

Description

Multiple improper input validation flaws were identified in some CLI commands of Zyxel USG/ZyWALL series firmware versions 4.09 through 4.71, USG FLEX series firmware versions 4.50 through 5.21, ATP series firmware versions 4.32 through 5.21, VPN series firmware versions 4.30 through 5.21, NSG series firmware versions 1.00 through 1.33 Patch 4, NXC2500 firmware version 6.10(AAIG.3) and earlier versions, NAP203 firmware version 6.25(ABFA.7) and earlier versions, NWA50AX firmware version 6.25(ABYW.5) and earlier versions, WAC500 firmware version 6.30(ABVS.2) and earlier versions, and WAX510D firmware version 6.30(ABTF.2) and earlier versions, that could allow a local authenticated attacker to cause a buffer overflow or a system crash via a crafted payload.

Category

6.1
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.99% Top 25%
Vendor Advisory zyxel.com
Affected: Zyxel USG/ZyWALL series firmware
Affected: Zyxel USG FLEX series firmware
Affected: Zyxel ATP series firmware
Affected: Zyxel VPN series firmware
Affected: Zyxel NSG series firmware
Affected: Zyxel NXC2500 firmware
Affected: Zyxel NAP203 firmware
Affected: Zyxel NWA50AX firmware
Affected: Zyxel WAC500 firmware
Affected: Zyxel WAX510D firmware
Published at:
Updated at:

References

Link Tags
https://www.zyxel.com/support/multiple-vulnerabilities-of-firewalls-AP-controllers-and-APs.shtml vendor advisory
http://seclists.org/fulldisclosure/2022/Jun/15 mailing list
http://packetstormsecurity.com/files/167464/Zyxel-Buffer-Overflow-Format-String-Command-Injection.html
http://packetstormsecurity.com/files/177036/Zyxel-zysh-Format-String-Proof-Of-Concept.html

Frequently Asked Questions

What is the severity of CVE-2022-26531?
CVE-2022-26531 has been scored as a medium severity vulnerability.
How to fix CVE-2022-26531?
To fix CVE-2022-26531, 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-2022-26531 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2022-26531 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2022-26531?
CVE-2022-26531 affects Zyxel USG/ZyWALL series firmware, Zyxel USG FLEX series firmware, Zyxel ATP series firmware, Zyxel VPN series firmware, Zyxel NSG series firmware, Zyxel NXC2500 firmware, Zyxel NAP203 firmware, Zyxel NWA50AX firmware, Zyxel WAC500 firmware, Zyxel WAX510D firmware.
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