CVE-2023-35138NAS326 firmware OS Command Injection
A command injection vulnerability in the “show_zysync_server_contents” function of the Zyxel NAS326 firmware version V5.21(AAZF.14)C0 and NAS542 firmware version V5.21(ABAG.11)C0 could allow an unauthenticated attacker to execute some operating system (OS) commands by sending a…
Published Dec 1, 2023 · Updated Aug 2, 2024
Key Facts
Patch in the next maintenance window- CVE-2023-35138 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting NAS326 firmware (Zyxel), NAS542 firmware (Zyxel).
- It is not listed in any known-exploited vulnerabilities catalog. No public exploit code is known.
- EPSS estimates a 40% probability of exploitation in the next 30 days.
- Fixed versions are available, including NAS326 firmware <=5.21\(aazf.14\)c0, NAS542 firmware <=5.21\(abag.11\)c0, NAS326 firmware 5.21\(aazf.14\)c0.
- Brandefense priority: patch in the next maintenance window, because of its high severity, although no exploitation is known.
Scores
CVSS v3.1
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
40%
Higher than 98.6% of all scored CVEs
Exploit maturity
None known
ATLAS score
41/100
Publication score, see How it works
Exploitation Verdict
KEV listed
Not listed
Federal due date
None
No federal due date
Ransomware use
Not reported
Attributed actors
None named
Exploit & Defence Guidance
Exploit maturity
None known
Public exploit code
0
Proof-of-concept links
In-the-wild evidence
0
Reports of active use
Advisories And Exploit References
- advisoryhttps://www.bleepingcomputer.com/news/security/zyxel-warns-of-multiple-critical-vulnerabilities-in-nas-devices/
- advisoryUSOM advisory
- advisoryhttps://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-authentication-bypass-and-command-injection-vulnerabilities-in-nas-products
Description
A command injection vulnerability in the “show_zysync_server_contents” function of the Zyxel NAS326 firmware version V5.21(AAZF.14)C0 and NAS542 firmware version V5.21(ABAG.11)C0 could allow an unauthenticated attacker to execute some operating system (OS) commands by sending a crafted HTTP POST request.
Affected Products
4 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| NAS326 firmwareZyxel | >= V5.21(AAZF.14)C0 | 5.21\(aazf.14\)c0 |
| NAS542 firmwareZyxel | >= V5.21(ABAG.11)C0 | 5.21\(abag.11\)c0 |
Patched Releases
NAS326 firmware
<=5.21\(aazf.14\)c0
NAS542 firmware
<=5.21\(abag.11\)c0
Timeline
Publicly disclosed
Dec 1, 2023
Last updated
Aug 2, 2024
Weakness Type
- CWE-78 Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
FAQ
Common Questions.
A command injection vulnerability in the “show_zysync_server_contents” function of the Zyxel NAS326 firmware version V5.21(AAZF.14)C0 and NAS542 firmware version V5.21(ABAG.11)C0 could allow an unauthenticated attacker to execute some operating system (OS) commands by sending a crafted HTTP POST request.
Affected: NAS326 firmware (Zyxel) versions >= V5.21(AAZF.14)C0; NAS542 firmware (Zyxel) versions >= V5.21(ABAG.11)C0. The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
Fixed versions are available, including NAS326 firmware <=5.21\(aazf.14\)c0, NAS542 firmware <=5.21\(abag.11\)c0, NAS326 firmware 5.21\(aazf.14\)c0.
Brandefense priority: patch in the next maintenance window, because of its high severity, although no exploitation is known.
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