CVE-2021-28100
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 · uneditedPriam uses File.createTempFile, which gives the permissions on that file -rw-r--r--. An attacker with read access to the local filesystem can read anything written there by the Priam process.
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 · moderate confidencePriam uses Java's File.createTempFile method which creates temporary files with default permissions (-rw-r--r--), making them world-readable. Any local attacker with filesystem read access can read sensitive data that Priam writes to these temp files, such as credentials or backup content.
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 dataall versionsCVSS 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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Identify if Priam is deployedLook for Priam JAR files, processes, or installation directories on the system. Check for 'priam' in running Java processes using 'jps -l' or 'ps aux | grep -i priam'. Search for priam*.jar files in common application directories.Affected if Priam is present on the system, as all versions are vulnerable.
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Locate temporary file creation codeSearch Priam source code or JAR files for usage of 'java.io.File.createTempFile'. Decompile the JAR or search within JAR contents for this method call.Affected if The code uses File.createTempFile, which creates files with default world-readable permissions (0644).
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Inspect actual temp file permissionsWhile Priam is running, check the permissions of files created in the system temp directory (typically /tmp). Use 'ls -la /tmp/' or monitor for newly created files with 'ls -la /tmp/filename' right after Priam operations.Affected if Temp files have permissions -rw-r--r-- (0644), meaning they are readable by all users on the system.
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Verify temp directory permissionsCheck the permissions of the directory where temp files are being created using 'ls -ld /tmp' or the configured java.io.tmpdir path.Affected if The temp directory has world-readable permissions (like /tmp with 1777), allowing any local user to read files within it.
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Check for sensitive data in temp filesExamine contents of temp files created by the Priam process. Use 'find /tmp -user <priam-user> -type f -newermt "1 hour ago"' to find recent temp files, then inspect their contents for credentials, keys, or backup data.Affected if Temp files contain sensitive information such as passwords, tokens, or backup content readable by other users.
If Priam is deployed and temp files are created with 0644 permissions in a world-readable temp directory, any local user can read sensitive data from those 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 dataReplace File.createTempFile with code that explicitly sets restrictive file permissions (e.g., using Files.setPosixFilePermissions to set 0600), or use a temp directory with restricted access, ensuring temp files are only readable by the process owner.
- Consultation2.0 h
- Implementation3.0 h
- Testing2.0 h
- Review / QA1.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-28100 — 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-2021-28100 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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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