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Punk-0.14
Security Advisories (1)
CVE-2026-75870 (2026-08-22)

Punk versions before 0.18 for Perl allow session cookie forgery via an empty default HMAC key when a session is declared without a secret. The session keyword freezes its options onto the application as given: it does not require a secret, warn, or refuse to start when one is absent. The cookie read and the write-back both default that key to the empty string, so a declaration with no secret option, or with an undefined or empty one, signs and verifies with a zero-length HMAC-SHA256 key. An attacker who knows the cookie format can then mint one offline carrying any contents the session holds, such as a user identifier or a role. Nothing marks the misconfiguration at runtime: cookies are well formed and sessions round-trip as expected.

Changes for version 0.14 - 2026-08-16

  • Requires from the C layer go through pk_require_once (an %INC check, then at most one eval per module per process) instead of a bare eval_pv per call. Perl's own eval_sv spends immortal references on every call on perls through 5.20 - whatever is evaluated, success or failure - and before 5.20 the immortals' refcounts are small and unprotected, so a path that re-requires per build (the markdown mount ran two) drains PL_sv_undef toward a segfault under punk dev's rebuild loop. Found by t/42-immortal-refcount.t on a CPAN smoker running perl 5.20.0; verified fixed on 5.20.3.
  • t/37-ua.t pins the per-request agent clones it compares by address: a freed clone's memory is the allocator's to hand straight back, so two DEAD clones can legally compare equal, which a smoker's malloc duly demonstrated. Held alive, distinct objects must differ.

Documentation

punk
the Punk command line

Modules

Punk
a MVC web framework
Punk::App
the per-application registry and boot compiler
Punk::Auth
the authentication battery
Punk::Auth::Password
password hashing
Punk::CORS
cross-origin resource sharing
Punk::CSRF
single-use CSRF tokens
Punk::Command
the punk command line: registry, dispatcher and commands
Punk::Config
YAML configuration with secrets kept out of the file
Punk::Context
the per-request object
Punk::Controller
base class for Punk controllers
Punk::DevError
the development error page
Punk::Future
an async result that runs on the loop, or blocks
Punk::Generate
scaffold a new Punk application
Punk::Headers
security response headers
Punk::Logger
a level-based logger
Punk::Model
the storage-agnostic model tier
Punk::Model::DBI
the default DBI backend for Punk models
Punk::Model::DBIx::Loop
a non-blocking backend for Punk models
Punk::Mount::Markdown
a directory of markdown as a documentation site
Punk::Mount::OpenAPI
the api mount: spec-first operations
Punk::Plugin
base class for Punk plugins
Punk::RateLimit
rate limiting and IP blocking over Hyperman's shared arena
Punk::Request
a lazy wrapper over the PSGI environment
Punk::Response
a response builder
Punk::Router
the compiled-at-boot route tables (XS)
Punk::Router::Scope
the handle an under returns
Punk::SSE
a Server-Sent Events stream
Punk::SendFile::Reader
the bounded body of a ranged send_file response
Punk::Session
signed cookie sessions
Punk::Static
serving files from a directory
Punk::Test
an in-process test client for Punk applications
Punk::Test::WS
a pure-Perl RFC 6455 codec for testing WebSocket servers
Punk::Test::WS::Conn
the client side of one WebSocket connection
Punk::UA
the outbound HTTP agent on the context
Punk::Upload
an uploaded file from a multipart form
Punk::Validate
collecting request validation
Punk::View::Stencil
the Template::Stencil view engine
Punk::Views
the pluggable view engine registry (XS)
Punk::WebSocket
a WebSocket connection
Punk::WebSocket::Room
pub/sub groups of WebSocket connections

Provides

BenchCat
in bench/apps/cat-lib/BenchCat.pm
BenchCat::Controller::Root
in bench/apps/cat-lib/BenchCat/Controller/Root.pm

Examples

Other files