CVE-2026-53757: Emlog path traversal in ZIP extraction enables RCE

CVE-2026-53757 · Severity: info · CVSS 8.8 · Published 2026-09-04

Emlog is an open-source website building system that allows administrators to upload plugins and templates as ZIP files. In versions 2.6.29 and earlier, a path traversal vulnerability in the ZIP extraction function allows authenticated attackers to overwrite critical system files like config.php, resulting in immediate remote code execution with web server privileges. This affects plugin uploads, template uploads, and store updates.

Technologies: Emlog. Vendors: Emlog.

Quick answers

Is CVE-2026-53757 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-53757 being exploited in the wild.
How severe is CVE-2026-53757?
Informational severity, with a CVSS score of 8.8, published 4 September 2026.
Which products and versions are affected?
Emlog 2.6.29 and prior.
Is there a fix for CVE-2026-53757?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-53757 attacked?
It is attacked over the network, in a web application.
Am I affected by CVE-2026-53757?
Check whether you run Emlog 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

The vulnerability is a classic Zip Slip path traversal flaw in the emUnZip() function (include/lib/common.php, lines 768–808). The function uses PHP's ZipArchive::extractTo() to extract all ZIP entries without validating individual entry paths for ../ sequences; only the first entry's subdirectory structure is checked. An attacker with admin credentials can craft a malicious ZIP containing entries with paths like "myplugin/../../config.php" to write arbitrary files outside the intended extraction directory. The flaw is exploitable on PHP 7.x and early PHP 8.0.x; later PHP versions may normalize traversal sequences at runtime, but the application performs no path sanitization. The attack vector is authenticated but the impact is critical (RCE via config.php overwrite). No patches are currently available.

Affected products

  • Emlog Emlog 2.6.29 and prior

Timeline

  • 2026-06-10: disclosed: GHSA-gjj4-37r4-mf5g published
  • 2026-09-04: advisory: CVE-2026-53757 published on NVD

References

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