Service interrupt via EOF read loop
Published Mar 19, 2021 · Updated Feb 13, 2025
Excessive iteration in Apache PDFBox 2.0.22 and earlier allows attackers to cause a service interrupt via a crafted PDF. The PDFBox random-access readFully implementations treated an end-of-file read as zero bytes, so a loop waiting for the requested length never advanced and continued indefinitely. Loading the file requires a parser to process attacker-supplied PDF data; the bounded impact is a hung PDF-processing operation without evidence of data disclosure or modification.
Summary
What happened
Excessive iteration in Apache PDFBox 2.0.22 and earlier allows attackers to cause a service interrupt via a crafted PDF. The PDFBox random-access readFully implementations treated an end-of-file read as zero bytes, so a loop waiting for the requested length never advanced and continued indefinitely. Loading the file requires a parser to process attacker-supplied PDF data; the bounded impact is a hung PDF-processing operation without evidence of data disclosure or modification.
The record
- CVE
- CVE-2021-27807
- Published
- Mar 19, 2021
- Updated
- Feb 13, 2025
- Vendor
- The Apache Software Foundation
- Product
- Apache PDFBox
- Classifications
- CWE-834, T1499.002
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Mar 19, 2021CVE publishedPublication date reported by the CVE source.
- Feb 13, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=Apache PDFBox <=2.0.22
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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