CVE-2026-33642

CRITICALNVD 9.89.8—
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 9.8 under NVD CVSS v3. EPSS exploit probability: 0.3%, top 79% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
Elevated
9.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 9.8Exploit: Elevated riskExposed: 0

A fix is available — apply it.

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.

CVSS v3
9.8
EG Score
9.8(medium)
EG Risk
75(Attend)
EG Risk 75/100SSVC: Attend

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity98% × 45%
Exploitation40% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
0%
EPSS %ILE
21%
KEV
Not listed

Published

May 19, 2026

Last Modified

July 24, 2026

Advisory Details (2)

Auto-updated Sep 18, 2026
🔬 Proof of concept available. Patch available. Sources: github_commit, github.
github Patch Available🟡 PoC Available

Heap Buffer Over-Read/Write via Integer Overflow in `compose_rectangles` Bounds Check · Advisory · kovidgoyal/kitty · GitHub

https://github.com/kovidgoyal/kitty/security/advisories/GHSA-qfgm-2c64-6x3x
github_commit

commit e9661f0f3afb (kovidgoyal/kitty)

Fix landed in kovidgoyal/kitty commit e9661f0f3afb — awaiting tagged release

https://github.com/kovidgoyal/kitty/commit/e9661f0f3afb4e4dbffa509adfb3df3c9780ad34

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntukitty-terminfo (0.41.1-2+deb13u1build0.25.10.1) @ questing2026-08-23ubuntu

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(3 across 3 ecosystems)
Debian:12(1)
PackageVulnerable rangeFixed inDependents
kitty0.26.5-5 ... 0.48.2-1 (39 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
kitty0.41.1-20.41.1-2+deb13u1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
kitty0.41.1-2 ... 0.46.2-1 (9 versions)0.47.0-1—

Weakness Classification(3)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

All Vendor Advisories

(1)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 7× in last 7d / 32× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 257 total refreshes for this CVE.

  1. 2026-09-20 20:15 UTCEPSS rescore
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-18 19:28 UTCEPSS rescore
  4. 2026-09-17 19:30 UTCEPSS rescore
  5. 2026-09-16 14:08 UTCEPSS rescore
  6. 2026-09-16 05:15 UTCEPSS rescore
  7. 2026-09-15 03:11 UTCEPSS rescore
  8. 2026-09-13 16:47 UTCEPSS rescore
  9. 2026-09-12 15:01 UTCEPSS rescore
  10. 2026-09-11 17:23 UTCOSV refresh
  11. 2026-09-11 14:53 UTCEPSS rescore
  12. 2026-09-11 09:37 UTCEPSS rescore
  13. 2026-09-10 09:34 UTCEPSS rescore
  14. 2026-09-08 22:00 UTCEPSS rescore
  15. 2026-09-07 16:01 UTCEPSS rescore
  16. 2026-09-06 13:47 UTCEPSS rescore
  17. 2026-09-04 05:06 UTCEPSS rescore
  18. 2026-09-02 14:11 UTCEPSS rescore
  19. 2026-09-01 13:53 UTCEPSS rescore
  20. 2026-09-01 04:39 UTCEPSS rescore
  21. 2026-09-01 04:39 UTCEPSS rescore
  22. 2026-08-30 19:17 UTCEPSS rescore
  23. 2026-08-30 01:22 UTCEPSS rescore
  24. 2026-08-28 21:41 UTCEPSS rescore
  25. 2026-08-27 14:25 UTCEPSS rescore
Show 75 more
  1. 2026-08-26 14:46 UTCEPSS rescore
  2. 2026-08-25 13:49 UTCEPSS rescore
  3. 2026-08-24 14:17 UTCEPSS rescore
  4. 2026-08-23 21:11 UTCVendor advisory
  5. 2026-08-23 17:00 UTCEG score recompute
  6. 2026-08-23 17:00 UTCVendor advisory
  7. 2026-08-23 00:19 UTCEPSS rescore
  8. 2026-08-21 23:49 UTCEPSS rescore
  9. 2026-08-21 23:37 UTCEG score recompute
  10. 2026-08-21 23:37 UTCVendor advisory
  11. 2026-08-20 22:55 UTCEPSS rescore
  12. 2026-08-20 22:55 UTCEPSS rescore
  13. 2026-08-20 19:00 UTCEG score recompute
  14. 2026-08-20 19:00 UTCVendor advisory
  15. 2026-08-19 17:03 UTCEPSS rescore
  16. 2026-08-18 13:48 UTCEPSS rescore
  17. 2026-08-17 14:02 UTCEG score recompute
  18. 2026-08-17 14:02 UTCVendor advisory
  19. 2026-08-17 13:47 UTCEPSS rescore
  20. 2026-08-17 09:59 UTCVendor advisory
  21. 2026-08-16 16:56 UTCEG score recompute
  22. 2026-08-16 16:56 UTCVendor advisory
  23. 2026-08-16 14:56 UTCEPSS rescore
  24. 2026-08-16 07:38 UTCVendor advisory
  25. 2026-08-16 03:34 UTCEG score recompute
  26. 2026-08-16 03:34 UTCVendor advisory
  27. 2026-08-16 02:14 UTCEPSS rescore
  28. 2026-08-15 02:26 UTCEG score recompute
  29. 2026-08-15 02:26 UTCVendor advisory
  30. 2026-08-15 01:30 UTCEPSS rescore
  31. 2026-08-14 22:23 UTCVendor advisory
  32. 2026-08-14 18:20 UTCVendor advisory
  33. 2026-08-14 14:16 UTCVendor advisory
  34. 2026-08-14 10:13 UTCVendor advisory
  35. 2026-08-14 06:10 UTCVendor advisory
  36. 2026-08-14 02:06 UTCEG score recompute
  37. 2026-08-14 02:06 UTCVendor advisory
  38. 2026-08-13 22:00 UTCEPSS rescore
  39. 2026-08-13 08:26 UTCVendor advisory
  40. 2026-08-13 04:22 UTCVendor advisory
  41. 2026-08-13 00:19 UTCVendor advisory
  42. 2026-08-12 20:15 UTCVendor advisory
  43. 2026-08-12 16:11 UTCEG score recompute
  44. 2026-08-12 16:11 UTCVendor advisory
  45. 2026-08-12 13:50 UTCEPSS rescore
  46. 2026-08-12 11:59 UTCVendor advisory
  47. 2026-08-11 22:54 UTCVendor advisory
  48. 2026-08-11 18:47 UTCVendor advisory
  49. 2026-08-11 13:53 UTCEG score recompute
  50. 2026-08-11 13:53 UTCVendor advisory
  51. 2026-08-11 08:44 UTCVendor advisory
  52. 2026-08-11 04:41 UTCVendor advisory
  53. 2026-08-11 00:38 UTCEG score recompute
  54. 2026-08-11 00:38 UTCVendor advisory
  55. 2026-08-11 00:00 UTCEPSS rescore
  56. 2026-08-10 14:04 UTCVendor advisory
  57. 2026-08-10 09:59 UTCVendor advisory
  58. 2026-08-10 05:56 UTCVendor advisory
  59. 2026-08-10 01:53 UTCVendor advisory
  60. 2026-08-09 21:50 UTCVendor advisory
  61. 2026-08-09 17:47 UTCEG score recompute
  62. 2026-08-09 17:47 UTCVendor advisory
  63. 2026-08-09 13:46 UTCEPSS rescore
  64. 2026-08-09 13:44 UTCVendor advisory
  65. 2026-08-09 09:41 UTCVendor advisory
  66. 2026-08-09 05:38 UTCVendor advisory
  67. 2026-08-09 01:35 UTCEG score recompute
  68. 2026-08-09 01:35 UTCVendor advisory
  69. 2026-08-08 16:37 UTCEPSS rescore
  70. 2026-08-08 14:03 UTCVendor advisory
  71. 2026-08-08 09:56 UTCVendor advisory
  72. 2026-08-08 05:53 UTCVendor advisory
  73. 2026-08-08 01:50 UTCVendor advisory
  74. 2026-08-07 21:46 UTCVendor advisory
  75. 2026-08-07 17:43 UTCEG score recompute

Related CVEs(same vendor + same CWE)

Same vendor

1 shown

ubuntu:USN-8442-1

Frequently asked(5)

What is CVE-2026-33642?
CVE-2026-33642 is a critical vulnerability published on May 19, 2026. Kitty is a cross-platform GPU based terminal. In versions 0.46.2 and below, the handlecomposecommand() 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…
When was CVE-2026-33642 disclosed?
CVE-2026-33642 was first published in the National Vulnerability Database on May 19, 2026, with the most recent update on July 24, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-33642 actively exploited?
CVE-2026-33642 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 78.6% of all scored CVEs.
What is the CVSS score of CVE-2026-33642?
CVE-2026-33642 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2026-33642?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-33642, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-33642

Explore →

Is Your Infrastructure Affected by CVE-2026-33642?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs