CVE-2026-9190: Request Smuggling (CVSS 9.1)

Description

An HTTP request smuggling vulnerability in the HTTP App Server of Progress MarkLogic Server before 11.3.6 and 12.0.3 allows a remote attacker to bypass authentication and authorization checks, hijack a legitimate user's session, or capture credentials. The vulnerability occurs when a crafted HTTP request containing both Content-Length and Transfer-Encoding headers causes a reverse proxy and MarkLogic Server to interpret request boundaries differently.

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CVSS v3.1 Score

9.1

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Weakness Type (CWE)

CWE-444 CWE-444

References

Other References

https://community.progress.com/s/article/Marklogic-Critical-Security-Alert-Bulletin-August-2026

Frequently Asked Questions

What is CVE-2026-9190? +

An HTTP request smuggling vulnerability in the HTTP App Server of Progress MarkLogic Server before 11.3.6 and 12.0.3 allows a remote attacker to bypass authentication and authorization checks, hijack a legitimate user's session, or capture credentials. The vulnerability occurs when a crafted HTTP request containing both Content-Length and Transfer-Encoding headers causes a reverse proxy and MarkLogic Server to interpret request boundaries differently. It has a CVSS v3.1 base score of 9.1 (CRITICAL).

How severe is CVE-2026-9190? +

CVE-2026-9190 has a CVSS v3.1 score of 9.1 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

How do I check if I'm vulnerable to CVE-2026-9190? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2026-9190