CVE-2026-54056: Kitty has an arbitrary file overwrite via symlink following in `kitten dnd` remote drop staging

Vulnerability summary

CVE-2026-54056 is a high (CVSS 7.6) Link Following vulnerability in kovidgoyal kitty. EPSS estimates a 0.38% chance of exploitation in the next 30 days, higher than 30.8% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 12-06-2026
   PublishedVulnerability first disclosed.
2. 15-06-2026
   Last modifiedVulnerability information updated.

Description

Kitty is a cross-platform GPU based terminal. In versions 0.47.0 and 0.47.1, `kitten dnd` can allow a malicious remote drag-and-drop source to overwrite or truncate arbitrary files writable by the local kitty user. Remote `text/uri-list` drops are staged in a temporary directory, but on case-sensitive filesystems duplicate remote basenames are not de-duplicated. An attacker can first create a staged symlink and then send a same-name regular-file entry. The regular-file write uses `utils.CreateAt()` / `openat(O_RDWR|O_CREAT|O_TRUNC)` without `O_NOFOLLOW`, so it follows the attacker-created symlink and writes outside the staging directory before final overwrite confirmation runs. This appears related in class to the file-transfer symlink advisory, but it is a different bug: it affects `kitten dnd` remote drag-and-drop staging, uses different vulnerable code (`kittens/dnd/drop.go` and `tools/utils/file_at_fd.go`), and reproduces on commit `4aa4a5c0567a92553a8c20a88a4352da637fca5d`, after the file-transfer `O_NOFOLLOW` fix. Version 0.47.2 patches the issue.

• CWE-59Improper Link Resolution Before File Access ('Link Following')The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.