# CVE-2026-4795: Zyxel GS1200v3 series missing authorization in log files

Source: https://junglewise.ai/threats/cve-2026-4795-zyxel-gs1200v3-series-missing-authorization-in-log-files  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-26. Updated: 2026-05-26  
License: CC BY 4.0 with a link back

CVE-2026-4795 · Severity: medium · CVSS 6.5 · Published 2026-05-26

A security vulnerability has been identified in several Zyxel GS1200 series network switches, which are used to manage data traffic in small to medium-sized offices. An unauthorized person on the local network could exploit this flaw to access sensitive system configuration files. This could lead to the exposure of network settings and other administrative information, potentially helping an attacker plan further intrusions.

Vendors: [Zyxel](https://junglewise.ai/threats/vendors/zyxel).

## Quick answers

**Is CVE-2026-4795 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-4795 being exploited in the wild.

**How severe is CVE-2026-4795?** Medium severity, with a CVSS score of 6.5, published 26 May 2026.

**Which products and versions are affected?** Zyxel GS1200-10v3 through 1.00(ACPW.2)C0; Zyxel GS1200-5HPv3 through 1.00(ACPU.2)C0; Zyxel GS1200-5v3 through 1.00(ACPS.2)C0; Zyxel GS1200-8HPv3 through 1.00(ACPV.2)C0; and 1 more.

**Is there a fix for CVE-2026-4795?** A patch was published on 2026-05-26: Firmware patches released for all affected models. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-4795 attacked?** It is attacked from the adjacent network, in a network appliance.

**Am I affected by CVE-2026-4795?** Check whether you run Zyxel GS1200-10v3, Zyxel GS1200-5HPv3, Zyxel GS1200-5v3 or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A missing authorization vulnerability (CWE-862) exists in the firmware of Zyxel GS1200v3 series switches. The flaw allows an unauthenticated attacker with adjacent network access (LAN-based) to retrieve system configuration information by sending a specifically crafted HTTP request to access log files. This occurs because the device fails to properly restrict access to sensitive files containing configuration data. Successful exploitation results in high confidentiality impact as it exposes the device's internal settings. Zyxel has released firmware updates (v1.00(ACPS.3)C0 through v1.00(ACPW.3)C0 depending on the model) to address this issue.

## Affected products

- Zyxel GS1200-5v3 through 1.00(ACPS.2)C0
- Zyxel GS1200-8v3 through 1.00(ACPT.2)C0
- Zyxel GS1200-5HPv3 through 1.00(ACPU.2)C0
- Zyxel GS1200-8HPv3 through 1.00(ACPV.2)C0
- Zyxel GS1200-10v3 through 1.00(ACPW.2)C0

## Timeline

- 2026-05-26: disclosed: Initial release of the security advisory by Zyxel.
- 2026-05-26: patched: Firmware patches released for all affected models.

## References

- [https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-missing-authorization-vulnerability-in-gs1200v3-series-switches-05-26-2026](https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-missing-authorization-vulnerability-in-gs1200v3-series-switches-05-26-2026)