CVE-2026-33633Public exploitNetwork attack vector

Terminal crash via undersized PNG payload buffer

Published May 19, 2026 · Updated May 19, 2026

Heap buffer overflow in kitty before 0.47.0 allows attackers to crash the terminal via crafted APC graphics protocol input. In load_image_data(), a PNG transfer can trigger one buffer doubling, after which memcpy writes the full payload without rechecking capacity. Controlled data must reach terminal input through a local process, displayed file, or remote session; a crash is confirmed, while code execution remains unconfirmed.

CVSS severity7.5
High
EPSS probability0.38%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Heap buffer overflow in kitty before 0.47.0 allows attackers to crash the terminal via crafted APC graphics protocol input. In load_image_data(), a PNG transfer can trigger one buffer doubling, after which memcpy writes the full payload without rechecking capacity. Controlled data must reach terminal input through a local process, displayed file, or remote session; a crash is confirmed, while code execution remains unconfirmed.

The record

CVE
CVE-2026-33633
Published
May 19, 2026
Updated
May 19, 2026
Vendor
Kovid Goyal
Product
kitty
Classifications
CWE-122
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 19, 2026CVE publishedPublication date reported by the CVE source.
  2. May 19, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 0.47.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Kovid Goyal · kittyversion=< 0.47.0

Published CVSS scores

7.5GitHub, Inc.CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-122Heap-based Buffer Overflow

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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