Request smuggling via malformed chunked bodies
Published Jul 29, 2026 · Updated Jul 29, 2026
HTTP request smuggling in Apache Traffic Server allows remote attackers to desynchronize proxy traffic using malformed chunked bodies. The HTTP/1.1 chunked-body handling accepts malformed message framing that another server can parse differently, causing request-boundary disagreement on a reused connection. Apache has not disclosed the exact malformed syntax or parser operation; exploitation requires crafted network requests and a downstream peer that interprets the resulting byte stream differently.
Summary
What happened
HTTP request smuggling in Apache Traffic Server allows remote attackers to desynchronize proxy traffic using malformed chunked bodies. The HTTP/1.1 chunked-body handling accepts malformed message framing that another server can parse differently, causing request-boundary disagreement on a reused connection. Apache has not disclosed the exact malformed syntax or parser operation; exploitation requires crafted network requests and a downstream peer that interprets the resulting byte stream differently.
The record
- CVE
- CVE-2026-57834
- Published
- Jul 29, 2026
- Updated
- Jul 29, 2026
- Vendor
- The Apache Software Foundation
- Product
- Apache Traffic Server
- Classifications
- CWE-444, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 29, 2026CVE publishedPublication date reported by the CVE source.
- Jul 29, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=10.0.0 <=10.1.3
- Affected versionversion=8.0.0 <=8.1.9
- Affected versionversion=9.0.0 <=9.2.14
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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