rust/fuzz (cargo-fuzz, nightly, its own workspace with the same IronRDP
patches) has targets for the Telnet IAC parser, the IRC parser + state
machine + mIRC formatter, VNC framebuffer updates and decoders,
~/.ssh/config parsing and the update manifest. They reach the private
parsers through hidden entry points behind nexus-core's 'fuzzing'
feature. A nightly workflow runs each for two minutes and uploads any
crashing input. A first 45 s run of each locally found nothing.
Seeded pseudo-random input, biased towards each parser's control bytes,
is fed to the IRC line parser and state machine (plus mIRC formatting),
Telnet IAC negotiation, VNC framebuffer updates (including ZRLE behind a
real zlib stream, with a check that the decoders are actually reached),
~/.ssh/config parsing and the update manifest. None panic, and Telnet's
pending buffer stays bounded.
These run on stable in every CI run; they are not coverage-guided, so a
cargo-fuzz setup (nightly) remains a possible follow-up.
OSC 52 and VNC ServerCutText now go through one handler that honours
'allow remote clipboard' and always toasts the first line, so a silent
clipboard swap can't set up a paste into another shell (SEC-20261012-010).
Multi-line pastes into a terminal without bracketed paste ask first, with a
preview (SEC-20261012-017). The launch-time update check can be turned off
and the updater docs no longer claim it is opt-in; the unused GitHub
fallback is removed (SEC-20261012-013, F15).
Andy Dixon