Please report security issues privately through GitHub's private vulnerability reporting rather than opening a public issue.

This is a spare-time project; expect an acknowledgement within a week or so. There is no bounty.

The latest release only. There are no maintenance branches.

cindex and csearch are local command-line tools with no network access and no privileged operations, so the interesting inputs are the files they read:

• Files being indexed or searched. Contents are treated as bytes. Files containing NUL, invalid UTF-8, lines over 2000 bytes, more than 20,000 distinct trigrams, or larger than 1 GiB are skipped. File contents are never interpreted as anything but data.
• The index file. csearch memory-maps it. Every section offset, name index entry and posting index entry is validated when the index is opened, and a damaged file is reported as corrupt rather than trusted. This matters because an index is a file like any other and may not have been written by this program. If you find an index that causes a panic, an out-of-bounds read, or a hang, that is a bug worth reporting — tests/corruption.rs is where such a case belongs.
• The regular expression. Matching uses the regex crate, which has no backtracking and guarantees linear-time matching, so a pattern cannot cause catastrophic backtracking. Query analysis is bounded (MAX_SET), though a sufficiently large bounded repetition can still be slow to analyse.

There is one unsafe block in the library, in src/trigram.rs: an AVX2 kernel guarded by runtime feature detection, with its bounds checked against the scalar implementation in tests. Memory mapping in src/read.rs is unsafe by nature of the API — a file modified while mapped is undefined behaviour, which is why index replacement goes through an atomic rename rather than writing in place.

Indexing a directory means reading every file in it. Pointing cindex at somewhere you do not trust, or at secrets you do not want in an index file, is a decision for the person running it, not a vulnerability in the tool.