CVE-2023-28771
Zyxel Multiple Firewalls: OS Command Injection
As of , CVE-2023-28771 in Zyxel Multiple Firewalls is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch this week.
- Exploited
- Yes: CISA listed it on 31 May 2023
- US federal deadline
- 21 June 202321 days after CISA listed it. US federal civilian agencies must fix it by then.
- Used in ransomware campaigns
- Not known to CISA
- EPSS score
- 0.99Higher than 99% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
- EPSS when listed
- 0.00 on 31 May 2023EPSS on the day CISA listed it.
- Public exploit
- 1 Metasploit module
- Fix
- Vendor advice: www.zyxel.comLinks below, from CISA's entry.
What CISA says to do
Apply updates per vendor instructions.
CISA's required action
What the flaw is
Zyxel ATP, USG FLEX, VPN, and ZyWALL/USG firewalls allow for improper error message handling which could allow an unauthenticated attacker to execute OS commands remotely by sending crafted packets to an affected device.
CISA's description
Improper error message handling in Zyxel ZyWALL/USG series firmware versions 4.60 through 4.73, VPN series firmware versions 4.60 through 5.35, USG FLEX series firmware versions 4.60 through 5.35, and ATP series firmware versions 4.60 through 5.35, which could allow an unauthenticated attacker to execute some OS commands remotely by sending crafted packets to an affected device.
The CVE record's description, from Zyxel
- CVE published
- 25 April 2023
- Assigned by
- Zyxel
- CVSS
- 9.8 Critical (CVSS 3.1, from the CNA)
- CWE-78
- Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
- CISA SSVC, exploitation
- active
- CISA SSVC, automatable
- yes
- CISA SSVC, technical impact
- total
Timeline
- The CVE record was published.
- CISA added it to its list of exploited vulnerabilities.
- The US federal deadline to fix it.
Public exploits
Facts from Metasploit's module list and Exploit-DB's index; we never copy exploit code.
- Metasploit: Zyxel IKE Packet Decoder Unauthenticated Remote Code Executionexploit module, rank great
Multiple Firewalls: other exploited entries
| Vulnerability | Product | Our group | Listed | Deadline | EPSS |
|---|---|---|---|---|---|
| CVE-2022-30525OS Command Injection | Zyxel Multiple Firewalls | Patch this weekMetasploit module; EPSS 0.99 | 0.99 | ||
| CVE-2024-11667Path Traversal | Zyxel Multiple Firewalls | Patch this weekRansomware use | 0.03 | ||
| CVE-2023-33009Buffer Overflow | Zyxel Multiple Firewalls | Patch soon | 0.28 | ||
| CVE-2023-33010Buffer Overflow | Zyxel Multiple Firewalls | Patch soon | 0.29 |
Read further
- CVE recordcve.org
- NVD entrynvd.nist.gov
- CISA's catalogcisa.gov
- EPSS for this CVEapi.first.org