# CVE-2026-93903: LiteSpeed Web Server internal redirect URL validation bypass

Source: https://junglewise.ai/threats/cve-2026-93903-litespeed-web-server-lsws-before-6-3-7-build-1-mishandles  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-30. Updated: 2026-09-30  
License: CC BY 4.0 with a link back

CVE-2026-93903 · Severity: info · Published 2026-09-30

LiteSpeed Web Server is a high-performance web server used to host and serve websites. Before version 6.3.7 build 1, it failed to properly validate internal redirect URLs in certain edge cases, which could allow an attacker to bypass intended security restrictions or redirect users to unintended locations. This vulnerability was addressed in 6.3.7 build 1 and later versions.

Vendors: [LiteSpeed Technologies](https://junglewise.ai/threats/vendors/litespeed-technologies).

## Quick answers

**Is CVE-2026-93903 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-93903 being exploited in the wild.

**How severe is CVE-2026-93903?** Informational severity, published 30 September 2026.

**Which products and versions are affected?** LiteSpeed Technologies Web Server before 6.3.7 build 1.

**Is there a fix for CVE-2026-93903?** A patch was published on 2026-09-15: 6.3.7 build 1 released with fix Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-93903 attacked?** It is in a web application.

**Am I affected by CVE-2026-93903?** Check whether you run LiteSpeed Technologies Web Server 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 involves improper URL validation for internal redirects in LiteSpeed Web Server prior to 6.3.7 build 1. An attacker could craft requests that exploit corner cases in the validation logic to bypass security controls or cause unintended redirects. The fix applies stronger validation of internal redirect URLs as released in build 1 and further hardened in build 2 (6.3.7) and build 0 (6.4.0).

## Affected products

- LiteSpeed Technologies Web Server before 6.3.7 build 1

## Timeline

- 2026-09-30: disclosed
- 2026-09-15: patched: 6.3.7 build 1 released with fix

## References

- [https://docs.litespeedtech.com/lsws/changelog/](https://docs.litespeedtech.com/lsws/changelog/)
- [https://www.litespeedtech.com/products/litespeed-web-server/release-log](https://www.litespeedtech.com/products/litespeed-web-server/release-log)