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Mojolicious-9.47
⭐ Starred 2674 / Mojo::Reactor::EV
Security Advisories (2)
CVE-2026-15747 (2026-07-14)

Mojolicious versions from 4.59 before 9.48 for Perl expose a stable representation of the session CSRF token to a BREACH compression oracle. _csrf_token generates and caches one token per session and returns the same value on every call, and _csrf_field places that value in a hidden `csrf_token` input. When a response carrying the token also echoes attacker-controlled input and is gzip-compressed, the chosen values and the resulting compressed lengths form a BREACH oracle. An attacker able to query it can recover the token and pass csrf_protect validation.

CVE-2024-58134 (2025-05-03)

Mojolicious versions from 0.999922 for Perl uses a hard coded string, or the application's class name, as an HMAC session cookie secret by default. These predictable default secrets can be exploited by an attacker to forge session cookies.  An attacker who knows or guesses the secret could compute valid HMAC signatures for the session cookie, allowing them to tamper with or hijack another user’s session.

NAME

Mojo::Reactor::EV - Low-level event reactor with libev support

SYNOPSIS

use Mojo::Reactor::EV;

# Watch if handle becomes readable or writable
my $reactor = Mojo::Reactor::EV->new;
$reactor->io($first => sub ($reactor, $writable) {
  say $writable ? 'First handle is writable' : 'First handle is readable';
});

# Change to watching only if handle becomes writable
$reactor->watch($first, 0, 1);

# Turn file descriptor into handle and watch if it becomes readable
my $second = IO::Handle->new_from_fd($fd, 'r');
$reactor->io($second => sub ($reactor, $writable) {
  say $writable ? 'Second handle is writable' : 'Second handle is readable';
})->watch($second, 1, 0);

# Add a timer
$reactor->timer(15 => sub ($reactor) {
  $reactor->remove($first);
  $reactor->remove($second);
  say 'Timeout!';
});

# Start reactor if necessary
$reactor->start unless $reactor->is_running;

DESCRIPTION

Mojo::Reactor::EV is a low-level event reactor based on EV (4.32+).

EVENTS

Mojo::Reactor::EV inherits all events from Mojo::Reactor::Poll.

METHODS

Mojo::Reactor::EV inherits all methods from Mojo::Reactor::Poll and implements the following new ones.

again

$reactor->again($id);
$reactor->again($id, 0.5);

Restart timer and optionally change the invocation time. Note that this method requires an active timer.

new

my $reactor = Mojo::Reactor::EV->new;

Construct a new Mojo::Reactor::EV object.

one_tick

$reactor->one_tick;

Run reactor until an event occurs or no events are being watched anymore.

# Don't block longer than 0.5 seconds
my $id = $reactor->timer(0.5 => sub {});
$reactor->one_tick;
$reactor->remove($id);

recurring

my $id = $reactor->recurring(0.25 => sub {...});

Create a new recurring timer, invoking the callback repeatedly after a given amount of time in seconds.

start

$reactor->start;

Start watching for I/O and timer events, this will block until "stop" is called or no events are being watched anymore.

# Start reactor only if it is not running already
$reactor->start unless $reactor->is_running;

stop

$reactor->stop;

Stop watching for I/O and timer events.

timer

my $id = $reactor->timer(0.5 => sub {...});

Create a new timer, invoking the callback after a given amount of time in seconds.

watch

$reactor = $reactor->watch($handle, $readable, $writable);

Change I/O events to watch handle for with true and false values. Note that this method requires an active I/O watcher.

# Watch only for readable events
$reactor->watch($handle, 1, 0);

# Watch only for writable events
$reactor->watch($handle, 0, 1);

# Watch for readable and writable events
$reactor->watch($handle, 1, 1);

# Pause watching for events
$reactor->watch($handle, 0, 0);

SEE ALSO

Mojolicious, Mojolicious::Guides, https://mojolicious.org.