Local file disclosure via XMP entity expansion
Published Apr 1, 2021 · Updated Aug 3, 2024
XXE in pikepdf 1.3.0 through 2.9.2 allows attackers to read local files by supplying a PDF with crafted XMP metadata. The metadata loader passes XMP XML to lxml parsing routines whose default parser resolves external entities and permits network access. An application must process attacker-controlled PDF metadata; the demonstrated consequence is disclosure of files readable by that application's process.
Summary
What happened
XXE in pikepdf 1.3.0 through 2.9.2 allows attackers to read local files by supplying a PDF with crafted XMP metadata. The metadata loader passes XMP XML to lxml parsing routines whose default parser resolves external entities and permits network access. An application must process attacker-controlled PDF metadata; the demonstrated consequence is disclosure of files readable by that application's process.
The record
- CVE
- CVE-2021-29421
- Published
- Apr 1, 2021
- Updated
- Aug 3, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-611, T1005
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 1, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
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.
Weakness, pattern, technique
Public exploit references
- Upstream XXE regression testproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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