CVE-2026-58155

Analyzed Analyzed - Analysis Complete

Header Name Truncation in Apache Traffic Server

Publication date: 2026-07-29

Last updated on: 2026-08-03

Assigner: Apache Software Foundation

Description

Apache Traffic Server truncates over-long header names, allowing header aliasing, request smuggling, and policy bypass. This issue affects Apache Traffic Server: from 8.0.0 through 8.1.9, from 9.0.0 through 9.2.14, from 10.0.0 through 10.1.3. Users are recommended to upgrade to version 9.2.15 or 10.1.4, which fix the issue.

CVSS Scores

EPSS Scores

Probability:
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Meta Information

Published

2026-07-29

Last Modified

2026-08-03

Generated

2026-08-18

AI Q&A

2026-07-30

EPSS Evaluated

2026-08-17

NVD

CVE-2026-58155

EUVD

EUVD-2026-50209

Affected Vendors & Products

Vendor	Product	Version / Range
apache	traffic_server	From 10.0.0 (inc) to 10.1.4 (exc)
apache	traffic_server	From 8.0.0 (inc) to 8.1.9 (inc)
apache	traffic_server	From 9.0.0 (inc) to 9.2.15 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-444	The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.

Attack-Flow Graph

Executive Summary

Apache Traffic Server has a flaw where it truncates overly long header names. This allows attackers to create header aliases, enabling request smuggling and bypassing security policies.

Detection Guidance

Detecting this vulnerability requires monitoring Apache Traffic Server for unusual header handling or request smuggling attempts. Check logs for truncated or malformed headers and inspect network traffic for anomalies. No specific commands are provided in the context.

Impact Analysis

This vulnerability can lead to unauthorized access, data breaches, or service disruption by allowing attackers to smuggle requests or bypass security controls.

Compliance Impact

This vulnerability allows header aliasing, request smuggling, and policy bypass, which could lead to unauthorized data access or manipulation. Such risks may violate GDPR's data integrity and confidentiality requirements or HIPAA's safeguards for protected health information.

Mitigation Strategies

Upgrade Apache Traffic Server to version 9.2.15 or 10.1.4 or later to address the vulnerability.

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