CVE-2026-115825: HTTP::Server::PSGI versions before 1.0056 for Perl allow a single request to crash the server by declaring a large Content-Length
Robert Rothenberg 25 Oct 2026 16:56 UTC
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CVE-2026-115825 CPAN Security Group
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CVE ID: CVE-2026-115825
Distribution: Plack
Versions: before 1.0056
MetaCPAN: https://metacpan.org/dist/Plack
VCS Repo: https://github.com/plack/Plack
HTTP::Server::PSGI versions before 1.0056 for Perl allow a single
request to crash the server by declaring a large Content-Length
Description
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HTTP::Server::PSGI versions before 1.0056 for Perl allow a single
request to crash the server by declaring a large Content-Length.
The request body is read with sysread() calls sized by the remaining
Content-Length. Perl grows the read buffer to the requested length
before any data arrives, so the server tries to allocate as much memory
as the client declares.
A remote attacker can send one request with a large Content-Length and
a few body bytes, and perl exits with an out-of-memory error before the
application is called. HTTP::Server::PSGI runs as a single process, so
the server stays down until restarted.
Problem types
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- CWE-789 Memory Allocation with Excessive Size Value
Solutions
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Upgrade to Plack 1.0057 or later.
References
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https://github.com/plack/Plack/commit/11545871cadc5df1b744cebb429cfeb4ebc1069a.patch
https://metacpan.org/release/MIYAGAWA/Plack-1.0056/changes