Zyxel Releases Patch for Critical Firewall OS Command Injection Vulnerability
Vulnerabilities mentionedAll →
| CVE | Vulnerability | CVSS | EPSS | Flags | Affected | Exposure | Published |
|---|---|---|---|---|---|---|---|
| CVE-2022-0556 | A local privilege escalation vulnerability caused by incorrect permission assignment in some directories of the Zyxel AP Configurator (ZAC) version 1.1.4, which A local privilege escalation vulnerability caused by incorrect permission assignment in some directories of the Zyxel AP Configurator (ZAC) version 1.1.4, which could allow an attacker to execute arbitrary code as a local administrator. NVD description · AI analysis pending | 7.8 | <1% |
| — | ||
| CVE-2022-26413 +1 in the same advisory: …26414 | A command injection vulnerability in the CGI program of Zyxel VMG3312-T20A firmware version 5.30(ABFX.5)C0 could allow a local authenticated attacker to execute A command injection vulnerability in the CGI program of Zyxel VMG3312-T20A firmware version 5.30(ABFX.5)C0 could allow a local authenticated attacker to execute arbitrary OS commands on a vulnerable device via a LAN interface. NVD description · AI analysis pending | 8.0 group max | <1% |
| — | ||
| CVE-2022-30525 | OS Command Injection in Zyxel Firewalls Enables Remote Command Execution CVE-2022-30525 is an OS command injection vulnerability (CWE-78) in the CGI program of certain Zyxel firewall firmware versions. By sending crafted requests to the vulnerable CGI program, an attacker can modify specific files on the appliance and inject and execute operating system commands. Successful exploitation yields command execution on the firewall itself, allowing an attacker to alter device files/configuration and potentially pivot into the protected network — the class of edge-device flaw commonly targeted by ransomware operators (ransomware use in this case is not yet confirmed). Organizations running affected Zyxel firewalls, particularly those with management interfaces reachable from the internet, are at risk. Exploitation is confirmed in the wild: the flaw was added to CISA's KEV on 2022-05-16, EPSS assigns a 99.9% 30-day exploitation probability (100th percentile), and no public PoC is catalogued yet. Do: Apply Zyxel's fixed firmware per the vendor's instructions immediately, as required by the CISA KEV listing. Until patched, restrict HTTP/HTTPS management access to the firewall to trusted source addresses only. Because exploitation is confirmed in the wild, prioritize internet-facing Zyxel firewalls and review devices for indicators of compromise such as modified configurations or unexpected administrative changes. | 9.8 | 100% | KEV PoC ×3 |
| large≈ tens of thousands of internet-exposed Zyxel firewall management interfaces (order of magnitude 10k–100k devices) |
Full article311 words · extracted from thehackernews.com · click to collapse
Ravie LakshmananMay 13, 2022
Zyxel has moved to address a critical security vulnerability affecting Zyxel firewall devices that enables unauthenticated and remote attackers to gain arbitrary code execution.
"A command injection vulnerability in the CGI program of some firewall versions could allow an attacker to modify specific files and then execute some OS commands on a vulnerable device," the company said in an advisory published Thursday.
Cybersecurity firm Rapid7, which discovered and reported the flaw on April 13, 2022, said that the weakness could permit a remote unauthenticated adversary to execute code as the "nobody" user on impacted appliances.
Tracked as CVE-2022-30525 (CVSS score: 9.8), the flaw impacts the following products, with patches released in version ZLD V5.30 -
- USG FLEX 100(W), 200, 500, 700
- USG FLEX 50(W) / USG20(W)-VPN
- ATP series, and
- VPN series
Rapid 7 noted that there are at least 16,213 vulnerable Zyxel devices exposed to the internet, making it a lucrative attack vector for threat actors to stage potential exploitation attempts.
The cybersecurity firm also pointed out that Zyxel silently issued fixes to address the issue on April 28, 2022 without publishing an associated Common Vulnerabilities and Exposures (CVE) identifier or a security advisory. Zyxel, in its alert, blamed this on a "miscommunication during the disclosure coordination process."
"Silent vulnerability patching tends to only help active attackers, and leaves defenders in the dark about the true risk of newly discovered issues," Rapid7 researcher Jake Baines said.
The advisory comes as Zyxel addressed three different issues, including a command injection (CVE-2022-26413), a buffer overflow (CVE-2022-26414), and a local privilege escalation (CVE-2022-0556) flaw, in its VMG3312-T20A wireless router and AP Configurator that could lead to arbitrary code execution.
Found this article interesting? Follow us on Google News, Twitter and LinkedIn to read more exclusive content we post.
Text extracted automatically; images, tables and formatting may be missing. Original: https://thehackernews.com/2022/05/zyxel-releases-patch-for-critical.html