A buffer overflow vulnerability in the ID processing function in Zyxel ATP series firmware versions 4.32 through 5.36 Patch 1, USG FLEX seri
Affects Zyxel ATP, USG FLEX, VPN, and ZyWALL/USG firmware across ZLD V4.25 to V5.36 Patch 1, depending on the model. CVSS rates it critical at 9.8. Fixed in ZLD V5.36 Patch 2.
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Listed in CISA KEV
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Actively exploited
- Fix
- Fixed in ZLD V5.36 Patch 2
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
Zyxel ATP, USG FLEX, USG20(W)-VPN, VPN, and ZyWALL/USG series firmware are affected by this buffer overflow in the ID processing function. An unauthenticated attacker could exploit it to crash the device (denial of service) or run arbitrary code on it.
Summarized by anthropic/claude-haiku-5.5. Verify details against the original sources.
Read the original description
A buffer overflow vulnerability in the ID processing function in Zyxel ATP series firmware versions 4.32 through 5.36 Patch 1, USG FLEX series firmware versions 4.50 through 5.36 Patch 1, USG FLEX 50(W) firmware versions 4.25 through 5.36 Patch 1, USG20(W)-VPN firmware versions 4.25 through 5.36 Patch 1, VPN series firmware versions 4.30 through 5.36 Patch 1, ZyWALL/USG series firmware versions 4.25 through 4.73 Patch 1, could allow an unauthenticated attacker to cause denial-of-service (DoS) conditions and even a remote code execution on an affected device.
Timeline
- CVE published
- Added to CISA KEV
CISA has evidence of exploitation in the wild
- CISA remediation deadline
Due date for US federal agencies to patch
- Record last updated
- EPSS reached 10%
FIRST estimates at least a 10% chance of exploitation in the next 30 days
Affected versions
- Zyxel ATP series firmware
4.32 through 5.36 Patch 1
- Zyxel USG FLEX series firmware
4.50 through 5.36 Patch 1
- Zyxel USG FLEX 50(W) firmware
4.25 through 5.36 Patch 1
- Zyxel USG20(W)-VPN firmware
4.25 through 5.36 Patch 1
- Zyxel VPN series firmware
4.30 through 5.36 Patch 1
- Zyxel ZyWALL/USG series firmware
4.25 through 4.73 Patch 1
References 1
Questions about CVE-2023-33010
What does this mean?
The ID processing function contains a buffer overflow. An unauthenticated attacker could use it to cause denial-of-service conditions and possibly run code on the affected device.Source: zyxel.com
Am I affected, and how do I check?
Affected firmware is ZLD V4.32 to V5.36 Patch 1 on ATP series, V4.50 to V5.36 Patch 1 on USG FLEX series, V4.25 to V5.36 Patch 1 on USG FLEX 50(W) and USG20(W)-VPN, V4.30 to V5.36 Patch 1 on VPN series, and V4.25 to V4.73 Patch 1 on ZyWALL/USG series. Check the firmware version shown on the device's status or dashboard page to compare against these ranges.Source: zyxel.com
What should I do about it?
Upgrade to ZLD V5.36 Patch 2, which fixes the issue. No workaround is listed in the facts.Source: zyxel.com
Is it being exploited?
Yes. CISA added it to its Known Exploited Vulnerabilities catalog on 2023-06-05, which means it has evidence of attacks. No public exploit code is tracked.Source: cisa.gov, cve.now feed data