Ubuntu LinuxOperating system · Canonical
CVE-2021-32552
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-16 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 validate file types before reading, allowing it to follow symbolic links or open FIFOs. When this function is used by openjdk-16 package apport hooks, it can expose sensitive private data (such as credentials, configuration files, or other user-specific information) 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.
-
Verify apport is installedRun 'dpkg -l apport' on Debian/Ubuntu systems to see if the apport package is presentAffected if apport is installed and the version matches Ubuntu 18.04, 20.04, 20.10, 21.04, or 21.10
-
Locate the vulnerable read_file() functionExamine the file /usr/lib/python3/dist/apport/hookutils.py and search for the read_file() function definitionAffected if The read_file() function exists and lacks validation to check if the target is a regular file (no check for symlinks or FIFOs before opening)
-
Check if openjdk-16 is installedRun 'dpkg -l | grep openjdk-16' to see if the openjdk-16 package is present on the systemAffected if openjdk-16 package is installed
-
Verify openjdk-16 apport hooks existLook for hook files in /usr/share/apport/package-hooks/ directory that reference openjdk-16, or check /usr/lib/python3/dist/apport/hookutils.py for calls from openjdk-related hooksAffected if Apport hooks for openjdk-16 exist and utilize the read_file() function to access user-specific files
The system is affected if apport with the vulnerable read_file() function is present AND openjdk-16 with its apport hooks is installed, allowing local privilege escalation through symlink/FIFO traversal to expose sensitive user data.
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 the read_file() function in apport/hookutils.py to validate that the target path is a regular file and not a symbolic link or FIFO before reading, ensuring no sensitive data can be exposed through traversal attacks.
Fix this in Ubuntu Linux
Scoped from the published advisory
- Consultation2.0 h
- Implementation3.0 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 $2,800.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-32552 — 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-2021-32552 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
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- 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
- No spam, self-promotion, credentials, or personal data