CVE-2026-32854 (GCVE-0-2026-32854)

Vulnerability from cvelistv5 – Published: 2026-03-24 17:31 – Updated: 2026-03-27 03:52
VLAI?
Title
LibVNCServer httpd proxy NULL Pointer Dereference
Summary
LibVNCServer versions 0.9.15 and prior (fixed in commit dc78dee) contain null pointer dereference vulnerabilities in the HTTP proxy handlers within httpProcessInput() in httpd.c that allow remote attackers to cause a denial of service by sending specially crafted HTTP requests. Attackers can exploit missing validation of strchr() return values in the CONNECT and GET proxy handling paths to trigger null pointer dereferences and crash the server when httpd and proxy features are enabled.
Severity ?
6.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
CWE
  • CWE-476 - NULL pointer dereference
Assigner
References
Impacted products
Vendor Product Version
LibVNC LibVNCServer Affected: 0 , ≤ 0.9.15 (semver)
Unaffected: dc78dee51a7e270e537a541a17befdf2073f5314 (git)
Create a notification for this product.
Credits
Kazuma Matsumoto, a security researcher at GMO Cybersecurity by IERAE, Inc.
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  • 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.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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