Traffic ControlApplication · Apache
CVE-2020-17522
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 · uneditedWhen ORT (now via atstccfg) generates ip_allow.config files in Apache Traffic Control 3.0.0 to 3.1.0 and 4.0.0 to 4.1.0, those files include permissions that allow bad actors to push arbitrary content into and remove arbitrary content from CDN cache servers. Additionally, these permissions are potentially extended to IP addresses outside the desired range, resulting in them being granted to clients possibly outside the CDN arcitechture.
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 · high confidenceThe ORT (now atstccfg) tool in Apache Traffic Control generates ip_allow.config files with overly permissive access controls in versions 3.0.0-3.1.0 and 4.0.0-4.1.0. These permissive configurations allow unauthorized actors to inject or purge arbitrary content from CDN cache servers, and may extend these permissions beyond the intended IP ranges.
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 ControlApplication
>= 3.0.0, <= 3.1.0>= 4.0.0, <= 4.1.0CVSS 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
- Low
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/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.
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Identify Apache Traffic Control versionCheck the installed version of Apache Traffic Control using your package manager or by querying the Traffic Ops API endpoint /api/1.3/system/info with a valid admin sessionAffected if The installed version falls within 3.0.0 to 3.1.0 or 4.0.0 to 4.1.0 inclusive
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Locate ip_allow.config fileFind the ip_allow.config file on your Traffic Ops server. Default locations include /opt/traffic_ops/app/etc/ or /etc/traffic_ops/ depending on installationAffected if The file exists and was generated by the ORT/atstccfg tool in an affected version
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Inspect access control entries for content injectionOpen ip_allow.config and examine the PUSH and POST entries. Look for entries with src_ip set to 0.0.0.0/0 or any broad private IP ranges that are not explicitly documented in your network designAffected if Content injection (PUSH/POST) is permitted from IP ranges beyond your intended authorized subnets
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Inspect access control entries for content purgeExamine the PURGE entries in ip_allow.config. Check if purge permissions are granted to IP addresses or ranges not authorized for cache invalidation operationsAffected if Purge permissions are granted to unauthorized or overly broad IP ranges
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Verify IP range restrictions match intended boundariesCompare the IP ranges defined in ip_allow.config against your documented allowed IP list for CDN management. Check if any rules permit actions from addresses outside your defined trust boundaryAffected if The configuration includes IP addresses or networks that were not explicitly intended to have content push or purge privileges
You are affected if Apache Traffic Control version is 3.0.0-3.1.0 or 4.0.0-4.1.0 AND the ip_allow.config file contains overly permissive PUSH, POST, or PURGE rules allowing unauthorized IP addresses to inject or purge content.
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 Control to a patched version, or manually audit and restrict the ip_allow.config file permissions to limit content push/purge actions to only authorized IP ranges.
Fix this in Traffic Control
Scoped from the published advisory
- Consultation4.0 h
- Implementation8.0 h
- Testing6.0 h
- Review / QA4.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $6,176.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2020-17522 — 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-2020-17522 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
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- Version or environment caveats, and links to real fixes
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