Description
Web::Simple versions before 0.035 for Perl allocate a buffer sized by the Content-Length header for urlencoded body parameters. Web::Dispatch::ParamParser::get_unpacked_body_from reads an application/x-www-form-urlencoded body using a single read call, with no cap and the return value ignored. Perl's read grows the buffer to the requested length before reading, so the declared Content-Length determines the allocation. An attacker can trigger this through any route whose dispatch specification has a % body-parameter match, such as sub (POST + %name=), sending a Content-Length far larger than the body actually sent. No authentication is involved.
References3
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - EPSS — exploit probability
- 0% percentile: 43 · as of 8 November 2026
- CWE
- CWE-789
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