CVE-2026-33633: kovidgoyal kitty Heap-based Buffer Overflow

Vulnerability summary

CVE-2026-33633 is a high (CVSS 8.8) Heap-based Buffer Overflow vulnerability in kovidgoyal kitty. EPSS estimates a 0.46% chance of exploitation in the next 30 days, higher than 38.6% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 19-05-2026
   PublishedVulnerability first disclosed.
2. 20-05-2026
   Last modifiedVulnerability information updated.

Description

Kitty is a cross-platform GPU based terminal. Versions 0.46.2 and below contain a heap buffer overflow in load_image_data() that allows any process which can write to the terminal's stdin to crash kitty immediately. The vulnerability is triggered by a single APC graphics protocol command with a PNG format declaration (f=100) whose payload exceeds twice the initial buffer capacity. The overflow is attacker-controlled in both length and content, causing DoS and potentially escalation to RCE itself. This issue has been fixed in version 0.47.0.

• CWE-122Heap-based Buffer OverflowA heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().