What is the CVSS score of CVE-2026-42851?

CVE-2026-42851 has a CVSS 3.1 base score of 7.8 (High). CVSS vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.0%.

Which versions of Kitty terminal are affected by CVE-2026-42851?

Kitty terminal emulator versions prior to 0.47.0 contain a critical vulnerability that allows unauthorized code execution with full user privileges when viewing untrusted content-including remote…. A patch is available.

How to fix or mitigate CVE-2026-42851?

Within 24 hours: Identify all systems running Kitty and confirm affected versions (0.46.x and earlier). Within 7 days: Restrict use of Kitty for viewing untrusted content; deploy alternative terminal emulators (GNOME Terminal, iTerm2, xterm) for operations involving remote data; disable TUI applications in Kitty if feasible. Within 30 days: Apply vendor patch to version 0.47.0 or later immediately upon release and update all affected infrastructure.

Kitty terminal CVE-2026-42851

EUVD-2026-36555 HIGH

Code Injection (CWE-94)

2026-06-12 security-advisories@github.com

Python Code Injection RCE Kitty Suse

7.8

CVSS 3.1 · Vendor: github

Severity by source

Vendor (github) PRIMARY

7.8 HIGH

AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

vuln.today AI

7.8 HIGH

Bytes must reach a local kitty TTY (AV:L) and the user must render them (UI:R); no auth or privileges needed (PR:N), and arbitrary Python as the user yields full C/I/A impact.

3.1 AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

4.0 AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

SUSE

HIGH

qualitative

Primary rating from Vendor (github).

CVSS VectorVendor: github

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Attack Vector

Local

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

Patch available

Jun 12, 2026 - 21:01 EUVD

Analysis Generated

Jun 12, 2026 - 20:30 vuln.today

DescriptionCVE.org

Kitty is a cross-platform GPU based terminal. In versions prior to 0.47.0, a program able to write bytes to a kitty terminal - a remote SSH peer, a downloaded file viewed with cat, a log line, an email body rendered in less, an issue body in a TUI, etc. - can cause kitty to execute attacker-supplied Python inside the running kitty process, with the user's full privileges. There is no approval prompt, no remote-control permission requirement, no shell-integration interaction, no clipboard touch, and no editor interaction. Version 0.47.0 fixes the issue.

Articles & Coverage 1

News 5 New Python Vulnerabilities - 1 Critical, 4 High Severity Jun 13, 2026

AnalysisAI

Remote code execution in Kitty terminal emulator versions prior to 0.47.0 allows any process or remote peer that can write bytes to the terminal - including SSH sessions, file viewers like cat or less, log tailers, and TUI applications - to execute attacker-supplied Python code inside the running kitty process with full user privileges. Exploitation requires no approval prompt, no shell integration, no clipboard interaction, and no editor involvement, making any rendered untrusted content a viable injection vector. No public exploit identified at time of analysis, but the trivial trigger conditions and broad attack surface make this a high-priority patch.

Technical ContextAI

Kitty is a cross-platform, GPU-accelerated terminal emulator written largely in Python with a C rendering core. Like other modern terminals it interprets a wide range of escape sequences and control codes embedded in the byte stream printed to the TTY; the vulnerability is a CWE-94 (Improper Control of Generation of Code, 'Code Injection') flaw where one of these terminal protocol features can be coerced into evaluating arbitrary Python in the kitty process itself rather than merely altering display state. Because the injection happens at the terminal-output layer, anything that ultimately reaches stdout/stderr of a kitty window - SSH from a remote host, cat of a downloaded file, less rendering an email body, a TUI rendering an issue description, a log line - becomes a delivery channel. The affected component is Kitty itself (vendor kovidgoyal/kitty); no CPE strings were supplied with the advisory.

RemediationAI

Vendor-released patch: upgrade kitty to version 0.47.0 or later, which fully fixes the issue per the vendor advisory at https://github.com/kovidgoyal/kitty/security/advisories/GHSA-w98g-hpvr-r332. Until the upgrade can be deployed, avoid using kitty to view untrusted byte streams: do not cat, less, or tail untrusted files, downloaded artifacts, or remote logs in a kitty window, and prefer a hardened pager or strip control sequences (for example pipe through cat -v or col -b) when inspecting attacker-influenced content; be aware these workarounds break legitimate color/escape handling and are easy to forget in interactive use, so they are stopgaps rather than substitutes for patching. For SSH from untrusted hosts, consider routing through a different terminal emulator until 0.47.0 is rolled out.