LibVNCServer httpd proxy NULL Pointer Dereference
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- Present
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · Low
- Fix status
- Partial Red Hat: 3 without a fix
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-476.
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| LibVNC | LibVNCServer | up to 0.9.15 | — | Patch available | CNA |
- LibVNCServer VendorLibVNC Affected up to 0.9.15 Fixed in — Patch available CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:libvncserver_project:libvncserver:*:*:*:*:*:*:*:* | before 0.9.15 | Vulnerable | Libvncserver Project |
- cpe:2.3:a:libvncserver_project:libvncserver:*:*:*:*:*:*:*:* Versions before 0.9.15 Vulnerable ·Libvncserver Project
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix planned: Will not fix |
| Red Hat Enterprise Linux 9 | Affected | No fix yet |
Not affected: 1 product
- Red Hat Enterprise Linux 7
Timeline
- 2026-10-02 Threatist record created from CVE-2026-32854
References
More LibVNC vulnerabilities
- TI-2026-37265 libvncclient Tight decoder has an attacker-controlled heap out-of-bounds write CVSS 3.1HIGH 8.8
- TI-2019-11774 Heap-based buffer overflow in LibVNCServer CVSS 3.1HIGH 8.8
- TI-2026-32847 LibVNCClient Tight Gradient decoding allows malicious server-triggered heap/stack OOB writes CVSS 3.1HIGH 8.8
Sources
- CVE-2026-32854 · CVE Program
- CVE-2026-32854 · NVD
- FIRST EPSS
- CVE-2026-32854 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences