CVE-2026-54055: Kitty has an Arbitrary File Write via Symlink Race Condition in File Transmission Protocol

Severity: medium (CVSS 5.0 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-06-12 · updated 2026-10-26
Weakness: CWE-59

Description

Kitty is a cross-platform GPU based terminal. In versions prior to 0.47.2, a local privilege escalation vulnerability exists in kitty's file transmission protocol where a child process running in the terminal can write to arbitrary files on the filesystem by exploiting a TOCTOU (Time-of-Check-Time-of-Use) race condition between symlink validation and file creation. The `os.open()` call used to create files does not use `O_NOFOLLOW`, allowing an attacker to create a symlink between the initial stat check and the actual file open, causing the write to follow the symlink to an arbitrary destination. Version 0.47.2 fixes the issue.

Affected products

kovidgoyal kitty: before 0.47.2 — fixed in 0.47.2

How to fix

Upgrade to a fixed version: kovidgoyal kitty 0.47.2. Check the vendor advisory for mitigations.

References

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