Quick answer
Direct answer
Risk scores
| CVSS metric | What it means |
|---|---|
| Attack vector (AV:N) | Network: reachable remotely |
| Attack complexity (AC:L) | Low complexity |
| Privileges required (PR:N) | No privileges required |
| User interaction (UI:N) | No user interaction |
| Scope (S:C) | Scope changed: impact spreads beyond the component |
| Confidentiality (C:L) | Low confidentiality impact |
| Integrity (I:L) | Low integrity impact |
| Availability (A:H) | High availability impact |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:H
About Kovidgoyal Kitty
CVE-2026-33642 affects Kovidgoyal Kitty, a product from Kovidgoyal. Before acting, confirm where Kovidgoyal Kitty runs in your estate, who owns it and whether it is reachable from the internet, because exposure decides real risk more than the score alone.
What the flaw is
In plain terms: Kitty is a cross-platform GPU based terminal. In versions 0.46.2 and below, the handle_compose_command() function in kitty/graphics.c performs bounds validation on composition offsets using unsigned 32-bit arithmetic that is subject to integer wrapping, potentially leading to Heap Buffer Over-Read/Write. An attacker who can write escape sequences to a kitty terminal (e.g., via a malicious file, SSH login banner, or piped content) can supply crafted x_offset/y_offset values that pass the bounds check after wrapping but cause massive out-of-bounds heap memory access in compose_rectangles(). No user interaction is required. No non-default configuration is required. The attacker only needs the ability to produce output in a kitty terminal window. This issue has been fixed in version 0.47.0.
The weakness class is Out of Bounds Read. The program reads memory past the end of a buffer, leaking data or crashing.
Based on its CVSS vector, the flaw can be reached over the network, needs no login, and needs no user interaction. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.
Affected versions and timeline
| Field | Detail |
|---|---|
| Product | Kovidgoyal Kitty |
| Affected versions | Kitty before 0.47.0 |
| Published | May 19, 2026 |
| Last modified | Jul 24, 2026 |
| Added to CISA KEV | Not listed |
| Assigning CNA | security-advisories@github.com |
How to detect it
- Inventory every instance of Kovidgoyal Kitty and record the running version against the affected range above.
- Check external attack surface scans for internet facing instances of the component.
- Review logs on affected systems for unusual requests, errors or new processes around the vulnerable function.
- Confirm with an authenticated vulnerability scan once your scanner has a check for this CVE.
How to fix it
- Apply the fixed version of Kovidgoyal Kitty named in the vendor advisory.
- If patching must wait, restrict network access to the affected service and put it behind authentication or a web application firewall rule.
- Rescan after the change to prove the exposure is gone, then close the ticket.
CTEM action plan
| CTEM stage | What to do for this CVE |
|---|---|
| Scope | Add every business service that depends on Kovidgoyal Kitty to the current CTEM cycle. |
| Discover | Find all instances, including shadow and cloud deployments, and record versions and exposure. |
| Prioritize | Rank using EPSS and CVSS together with asset exposure and business impact. |
| Validate | Confirm the flaw is reachable and exploitable in your environment and that compensating controls work. |
| Mobilize | Assign the fix to the asset owner with a due date matched to the priority, then verify closure. |
CWE References
- CWE-125: Out of Bounds Read More CVEs with this weakness
- CWE-190: Integer Overflow More CVEs with this weakness
- CWE-787: Out of Bounds Write More CVEs with this weakness
Technical References
Frequently asked questions
Related CVEs
Kitty is a cross-platform GPU based terminal. In versions prior to 0.47.3, kitty's OSC 21 (color-control) query reply reflects attacker-controlled bytes, including newlines, into the shell's input without sanitization. Version 0.47.3 fixes the issue.
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.
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