TorApplication · Debian
CVE-2017-11565
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 · unediteddebian/tor.init in the Debian tor_0.2.9.11-1~deb9u1 package for Tor was designed to execute aa-exec from the standard system pathname if the apparmor package is installed, but implements this incorrectly (with a wrong assumption that the specific pathname would remain the same forever), which allows attackers to bypass intended AppArmor restrictions by leveraging the silent loss of this protection mechanism. NOTE: this does not affect systems, such as default Debian stretch installations, on which Tor startup relies on a systemd unit file (instead of this tor.init script).
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 tor.init script in Debian's tor package attempts to execute aa-exec (AppArmor's execution wrapper) from a hardcoded system pathname, but implements this incorrectly by assuming the pathname remains static forever. When this assumption fails, the aa-exec protection silently fails to activate, allowing Tor to run without AppArmor enforcement and enabling attackers to bypass intended AppArmor restrictions. This only affects systems using the init script for Tor startup, not those using systemd unit files.
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
TorApplication
= 0.2.9.11-1CVSS 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
- Unchanged
- Confidentiality
- None
- Integrity
- High
- Availability
- None
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/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.
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Identify the installed Tor versionRun `dpkg -l | grep tor` or `tor --version` to see the installed Debian Tor package versionAffected if Version equals 0.2.9.11-1 exactly
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Determine if Tor is started via the init scriptRun `systemctl status tor` or check if /etc/init.d/tor exists and is usedAffected if The init script /etc/init.d/tor is actively used to start Tor (not systemd)
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Inspect the tor.init script for aa-exec invocationExamine /etc/init.d/tor and search for the hardcoded aa-exec path (typically /usr/sbin/aa-exec) in the scriptAffected if The script contains aa-exec invocation but relies on a static pathname that may become invalid
You are affected if Tor version 0.2.9.11-1 is installed AND Tor is started using the /etc/init.d/tor script rather than systemd, causing AppArmor enforcement to silently fail.
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 dataIf the system uses the tor.init script (check with `systemctl status tor` or examining /etc/init.d/tor), replace it with systemd-based startup or update the aa-exec invocation to use a reliable method; default Debian stretch and later are unaffected.
Fix this in Tor
Scoped from the published advisory
- Consultation2.0 h
- Implementation1.0 h
- Testing2.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,696.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2017-11565 — 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-2017-11565 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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