Ubuntu LinuxOperating system · Canonical
CVE-2021-32553
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-17 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). When this function is used by openjdk-17 package apport hooks, it can inadvertently expose private data to other local users on the system by reading from unintended files accessible via symlink or FIFO.
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= 21.10
OpenjdkApplication
= 17CVSS 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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Verify apport is installedRun: dpkg -l | grep apport or check for /usr/share/apport/package-hooks/Affected if apport package is present on Ubuntu 18.04 through 21.10 systems
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Verify openjdk-17 is installedRun: java -version or dpkg -l | grep openjdk-17, or check for /usr/lib/jvm/java-17-openjdk*Affected if openjdk-17 package is installed on the system
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Check apport versionRun: python3 -c "import apport; print(apport.__version__)" or dpkg -s apport | grep VersionAffected if Version matches Ubuntu 18.04, 20.04, 20.10, 21.04, or 21.10 base packages
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Locate openjdk-17 apport hooksCheck for files in /usr/share/apport/package-hooks/ containing 'openjdk' or 'java', or search: find /usr/share/apport -name '*java*' -o -name '*openjdk*'Affected if Any openjdk-17 related hook files exist in the apport package-hooks directory
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Inspect read_file() function in hookutils.pyExamine /usr/lib/python3/dist-packages/apport/hookutils.py and locate the read_file() function - check if it contains os.path.islink or stat.S_ISLNK checks, or if it opens FIFOs without validationAffected if The read_file() function lacks symbolic link and FIFO validation checks
A user is affected if they have openjdk-17 installed on an Ubuntu system with an unpatched apport package, where openjdk-17 apport hooks can trigger the unsafe read_file() function to expose files via symlinks or FIFOs to local users.
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 check for and refuse to follow symbolic links, and avoid opening FIFOs; alternatively, ensure openjdk-17 apport hooks use safe file-reading methods that validate paths before reading.
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-2021-32553 — 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-2021-32553 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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