Vulnerability · Published Sep 25, 2026 · Assigned by Secur0
CVE-2026-95832Reflected unknown field names in the kitty colour control escape code allow command execution in the user's shell
Critical 9.3
In plain English
A critical-severity injection in kitty from Kovid Goyal. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 5% of all known vulnerabilities).
Official description
Improper Neutralization of Special Elements in Output Used by a Downstream Component in the colour control escape code handler in kitty from 0.47.3 before 0.49.0 allows a program writing to the terminal to execute an arbitrary command in the user's shell, because color_control() in kitty/window.py answers a query for an unrecognised field name by placing that field name into the reply, and write_escape_code_to_child() in kitty/screen.c then writes the reply to the pseudoterminal master, where it is not distinguishable from input typed by the user, without neutralising it for the shell that reads it. The payload is reduced to printable ASCII before the field name is echoed, which is the restriction introduced in 0.47.3 as the fix for CVE-2026-54057, and the record and field separators ; and = are consumed as delimiters, but every other printable character survives, which is sufficient to compose a shell command. A newline is available from handle_remote_ssh() in kitty/window.py, which writes the bytes yielded by get_ssh_data() in kittens/ssh/utils.py, the first of which begin with a newline, to the pseudoterminal master before any credential carried in the request is checked. The reply is framed as an OSC sequence carrying the escape code number, the field name, and the literal value ?. This results in execution of an attacker-chosen command with the privileges of the user running the terminal.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | kitty | no fix listed | DEBIAN-CVE-2026-95832 |
| Debian:13 | kitty | no fix listed | DEBIAN-CVE-2026-95832 |
| Debian:14 | kitty | no fix listed | DEBIAN-CVE-2026-95832 |
| Ubuntu:26.10 | kitty | no fix listed | UBUNTU-CVE-2026-95832 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Kovid Goyal | kitty | 0.47.3 – before 0.49.0 |
Weakness: CWE-74 · Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
References
- https://github.com/kovidgoyal/kitty/commit/03fbdad855490470233954bc810e517027e5e640 patch
- https://github.com/kovidgoyal/kitty/commit/57bb144d96c0f9d48a2b0a6d43c9a23d2a091cbf related
- https://github.com/kovidgoyal/kitty/releases/tag/v0.49.0 release-notes
- https://www.cve.org/CVERecord?id=CVE-2026-54057 related
- https://secur0.com/en/cna/cve-list/cve-2026-95832-kitty-color-control-command-execution third-party-advisory, technical-description