Ubuntu LinuxOperating system · Canonical
CVE-2021-32548
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-8 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 follows symbolic links and opens FIFOs (named pipes) without validation. When this function is used by openjdk-8 package apport hooks to collect crash data, it can inadvertently read and expose sensitive private data to other local users on the system.
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 Ubuntu versionRun 'lsb_release -r' or 'cat /etc/lsb-release' to get the exact Ubuntu release numberAffected if The version is 18.04, 20.04, 20.10, 21.04, or 21.10
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Verify openjdk-8 is installedRun 'dpkg -l | grep openjdk-8' or 'apt list --installed 2>/dev/null | grep openjdk-8'Affected if The openjdk-8 package is installed on the system
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Confirm apport service is enabledRun 'systemctl is-enabled apport' or check if /etc/default/apport exists and contains 'enabled=1'Affected if Apport is enabled and will execute crash handler hooks including the openjdk-8 hook
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Locate the openjdk-8 apport hookCheck for /usr/share/apport/package-hooks/source_openjdk-8.py or similar hook file in /usr/share/apport/package-hooks/Affected if The openjdk-8 apport hook file exists and would be triggered on Java crash reports
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Inspect the read_file() function in hookutilsExamine /usr/lib/python3/dist/apport/hookutils.py for the read_file() function implementationAffected if The read_file() function lacks validation for symbolic links and FIFOs (the vulnerable code pattern)
The system is affected if it runs an affected Ubuntu version (18.04, 20.04, 20.10, 21.04, or 21.10) with openjdk-8 installed and apport enabled, where the read_file() function in apport/hookutils.py does not validate symlinks/FIFOs before opening files.
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 dataModify read_file() to validate and reject symbolic links and FIFOs before opening files, or disable/restrict the openjdk-8 apport hook to prevent unauthorized file access.
Fix this in Ubuntu Linux
Scoped from the published advisory
- Consultation2.0 h
- Implementation4.0 h
- Testing3.0 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 $3,088.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-32548 — 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-2021-32548 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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