Local code execution via world-writable response cache
Published May 15, 2026 · Updated May 15, 2026
Deserialization in WWW::Mechanize::Cached before 2.00 allows local users to forge cached HTTP responses and execute code through a shared cache. The default Cache::FileCache creates /tmp/FileCache subdirectories with mode 0777, and _make_request passes SHA-1-keyed cache entries to Storable::thaw without establishing their integrity. Exploitation requires write access to the cache tree and a victim process that requests a predictable URL while a class with a side-effectful deserialization or destruction hook is loaded.
Summary
What happened
Deserialization in WWW::Mechanize::Cached before 2.00 allows local users to forge cached HTTP responses and execute code through a shared cache. The default Cache::FileCache creates /tmp/FileCache subdirectories with mode 0777, and _make_request passes SHA-1-keyed cache entries to Storable::thaw without establishing their integrity. Exploitation requires write access to the cache tree and a victim process that requests a predictable URL while a class with a side-effectful deserialization or destruction hook is loaded.
The record
- CVE
- CVE-2026-8612
- Published
- May 15, 2026
- Updated
- May 15, 2026
- Vendor
- Olaf Alders
- Product
- WWW::Mechanize::Cached
- Classifications
- CWE-732, CWE-502
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- May 15, 2026CVE publishedPublication date reported by the CVE source.
- May 15, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=0 <2.00
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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