CVE-2025-53537: libhtp — Fix

Description

LibHTP is a security-aware parser for the HTTP protocol and its related bits and pieces. In versions 0.5.50 and below, there is a traffic-induced memory leak that can starve the process of memory, leading to loss of visibility. To workaround this issue, set `suricata.yaml app-layer.protocols.http.libhtp.default-config.lzma-enabled` to false. This issue is fixed in version 0.5.51.

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CVSS v3.1 Score

7.5

HIGH

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

Weakness Type (CWE)

CWE-401 CWE-401

Affected Products

Vendor	Product	Versions
oisf	libhtp	< 0.5.51

References

Advisories & Patches

https://github.com/OISF/libhtp/commit/9037ea35110a0d97be5cedf8d31fb4cd9a38c7a7 https://github.com/OISF/libhtp/security/advisories/GHSA-v3qq-h8mh-vph7

Frequently Asked Questions

What is CVE-2025-53537? +

LibHTP is a security-aware parser for the HTTP protocol and its related bits and pieces. In versions 0.5.50 and below, there is a traffic-induced memory leak that can starve the process of memory, leading to loss of visibility. To workaround this issue, set `suricata.yaml app-layer.protocols.http.libhtp.default-config.lzma-enabled` to false. This issue is fixed in version 0.5.51. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2025-53537? +

CVE-2025-53537 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2025-53537? +

CVE-2025-53537 affects products from oisf, specifically: libhtp. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-53537? +

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-2025-53537