PT-2023-3608 · Zyxel · Zyxel Nxc2500+6

Lê Hữu Quang Linh + 1 · Published 2023-05-26 · Updated 2023-07-26 · CVE-2023-34140

Positive Technologies (AI Summary)

CVSS v3.1

6.5

Medium

Base vector

AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Name of the Vulnerable Software and Affected Versions Zyxel ATP series versions 4.32 through 5.36 Patch 2 Zyxel USG FLEX series versions 4.50 through 5.36 Patch 2 Zyxel USG FLEX 50(W) series versions 4.16 through 5.36 Patch 2 Zyxel USG20(W)-VPN series versions 4.16 through 5.36 Patch 2 Zyxel VPN series versions 4.30 through 5.36 Patch 2 Zyxel NXC2500 versions 6.10(AAIG.0) through 6.10(AAIG.3) Zyxel NXC5500 versions 6.10(AAOS.0) through 6.10(AAOS.4)

Description A buffer overflow vulnerability in the CAPWAP daemon could allow an unauthenticated, LAN-based attacker to cause denial of service (DoS) conditions by sending a crafted request. This issue is related to a buffer overflow in the memory, which can be exploited by a remote attacker to cause a denial of service.

Recommendations For Zyxel ATP series versions 4.32 through 5.36 Patch 2, update to a version later than 5.36 Patch 2. For Zyxel USG FLEX series versions 4.50 through 5.36 Patch 2, update to a version later than 5.36 Patch 2. For Zyxel USG FLEX 50(W) series versions 4.16 through 5.36 Patch 2, update to a version later than 5.36 Patch 2. For Zyxel USG20(W)-VPN series versions 4.16 through 5.36 Patch 2, update to a version later than 5.36 Patch 2. For Zyxel VPN series versions 4.30 through 5.36 Patch 2, update to a version later than 5.36 Patch 2. For Zyxel NXC2500 versions 6.10(AAIG.0) through 6.10(AAIG.3), update to a version later than 6.10(AAIG.3). For Zyxel NXC5500 versions 6.10(AAOS.0) through 6.10(AAOS.4), update to a version later than 6.10(AAOS.4). As a temporary workaround, consider disabling the CAPWAP daemon until a patch is available.

Fix

Buffer Overflow

Weakness Enumeration

CWE-120

Related Identifiers

BDU:2023-03891

CVE-2023-34140

Affected Products

Zyxel Atp Series

Zyxel Nxc2500

Zyxel Nxc5500

Zyxel Usg Flex 50(W) Series

Zyxel Usg Flex Series

Zyxel Usg20(W)-Vpn Series

Zyxel Vpn Series

References · 7

• https://osv.dev/vulnerability/CVE-2023-34140 · Vendor Advisory
• https://zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-vulnerabilities-in-firewalls-and-wlan-controllers · Vendor Advisory
• https://bdu.fstec.ru/vul/2023-03891 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2023-34140 · Security Note
• https://t.me/cvenotify/54517 · Telegram Post
• https://vuldb.com/ru/?id.234339 · Note
• https://t.me/cvenotify/55245 · Telegram Post