CVE-2026-32853 (GCVE-0-2026-32853)

Vulnerability from cvelistv5 – Published: 2026-03-24 17:30 – Updated: 2026-03-25 13:41
VLAI
Title
LibVNCServer UltraZip Encoding Heap Out-of-bounds Read
Summary
LibVNCServer versions 0.9.15 and prior (fixed in commit 009008e) contain a heap out-of-bounds read vulnerability in the UltraZip encoding handler that allows a malicious VNC server to cause information disclosure or application crash. Attackers can exploit improper bounds checking in the HandleUltraZipBPP() function by manipulating subrectangle header counts to read beyond the allocated heap buffer.
Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
Assigner
References
Impacted products
Vendor Product Version
LibVNC LibVNCServer Affected: 0 , ≤ 0.9.15 (semver)
Unaffected: 009008e2f4d5a54dd71f422070df3af7b3dbc931 (git)
Create a notification for this product.
Credits
Kazuma Matsumoto, a security researcher at GMO Cybersecurity by IERAE, Inc.
Show details on NVD website
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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