Ubuntu LinuxOperating system · Canonical
CVE-2021-32547
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 · uneditedIt was discovered that read_file() in apport/hookutils.py would follow symbolic links or open FIFOs. When this function is used by the openjdk-lts package apport hooks, it could expose private data to other local users.
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 read_file() function in apport/hookutils.py does not properly validate file paths before opening them, allowing it to follow symbolic links or open FIFOs (named pipes). When this function is used by openjdk-lts package apport hooks, a local user could potentially craft symlinks or FIFOs pointing to sensitive private data, exposing that data to other local users.
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
Ubuntu LinuxOperating system
= 18.04= 20.04= 20.10= 21.04= 21.10CVSS 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
- Local
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/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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Check if apport package is installedRun: dpkg -l apport or apt list --installed 2>/dev/null | grep apportAffected if apport is installed and the system runs one of the affected Ubuntu versions (18.04, 20.04, 20.10, 21.04, 21.10)
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Determine installed apport versionRun: dpkg -s apport 2>/dev/null | grep VersionAffected if The installed version has not received the CVE-2021-32547 patch (compare against vendor security notices for Ubuntu)
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Locate the vulnerable read_file() functionRun: find /usr -name hookutils.py 2>/dev/null and examine the read_file() function for symlink/FIFO validation logicAffected if The read_file() function lacks code to reject symlinks and FIFOs before opening files
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Check if openjdk-lts is installed with apport hooksRun: dpkg -l openjdk-* 2>/dev/null | grep -i lts and check for apport hook files in /usr/share/apport/package-hooks/Affected if openjdk-lts with associated apport hooks is present, allowing the vulnerable code path to be triggered
A user is affected if running an unpatched Ubuntu version (18.04-21.10) with apport installed and the read_file() function in apport/hookutils.py lacks symlink/FIFO validation, particularly when openjdk-lts apport hooks are present.
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 dataApply the vendor patch for CVE-2021-32547 to apport/hookutils.py to ensure read_file() properly validates and rejects symbolic links and FIFOs before reading, or upgrade to a patched version of the apport package.
Fix this in Ubuntu Linux
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-2021-32547 — 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-2021-32547 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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- 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
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