Traffic ServerApplication · Apache
CVE-2017-5660
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedThere is a vulnerability in Apache Traffic Server (ATS) 6.2.0 and prior and 7.0.0 and prior with the Host header and line folding. This can have issues when interacting with upstream proxies and the wrong host being used.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · moderate confidenceApache Traffic Server fails to properly handle Host headers with line folding (a deprecated HTTP header continuation format), causing requests to be routed to the wrong upstream host when ATS acts as a proxy. This can result in request routing to incorrect backends and potential data leakage or cache poisoning.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data
Traffic ServerApplication
<= 6.2.0= 6.2.1= 6.2.2= 7.0.0
Debian LinuxOperating system
= 9.0CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Changed
- Confidentiality
- None
- Integrity
- High
- Availability
- None
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
-
Check if Apache Traffic Server is installedRun `traffic_server -V` or ` trafficserver -V` to get the version, or check for the binary at typical locations like /usr/bin/traffic_serverAffected if The command returns a version number matching <= 6.2.0, 6.2.1, 6.2.2, or 7.0.0
-
Identify if ATS is configured as a proxyExamine the records.config or proxy.config files in the ATS configuration directory (typically /etc/trafficserver/) and look for proxy-related settings such as `proxy.config.http.proxy_enabled` or `CONFIG proxy.config.reverse_proxy.enabled` set to 1Affected if ATS is acting as a reverse proxy or forward proxy and the version is vulnerable
-
Verify Host header handling configurationCheck records.config for `proxy.config.http.host_folding` or similar settings related to Host header parsing. Also inspect any remap rules in remap.config that handle Host-based routingAffected if Host header handling is enabled or default, and the ATS version is vulnerable
-
Test for line folding in Host headersSend a manually crafted HTTP request with a folded Host header (e.g., `Host: example.com\r\n continuation`) to the ATS proxy port and observe whether the request is forwarded to an unexpected upstream based on the folded portionAffected if Requests with folded Host headers are processed and routed to a different backend than expected based on the primary Host value
You are affected if Apache Traffic Server version 6.2.0 or below, 6.2.1, 6.2.2, or 7.0.0 is installed and configured to proxy requests, allowing malformed Host headers with line folding to route traffic to incorrect backends.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataUpgrade Apache Traffic Server to a version beyond 7.0.0/6.2.0 that includes the fix, and/or implement strict Host header validation rules to reject malformed headers before processing.
Fix this in Traffic Server
Scoped from the published advisory
- Consultation3.0 h
- Implementation6.0 h
- Testing5.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,464.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2017-5660 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2017-5660 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data