CVE-2026-32854: LibVNCServer versions 0.9.15 and prior (fixed in commit dc78dee) contain null pointer dereference vulnerabilit

Q: How do I fix CVE-2026-32854?

libvncserver: upgrade to 0.9.15. Exact commands for each OS are on this page.

Q: Is CVE-2026-32854 being exploited?

CVE-2026-32854 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2026-32854 affect?

CVE-2026-32854 affects libvncserver. Severity is high (CVSS 7.5). 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 se

Q: How urgent is CVE-2026-32854?

Priority 59/100. High severity; EPSS top 7%: very likely to be exploited; Public exploit reference; Remotely exploitable, no login, no user action

This week

HIGH 7.5REMOTEUPGRADE

CVE-2026-32854 is a high-severity flaw (CVSS 7.5) affecting libvncserver. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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 wh

Why this priority

High severity
EPSS top 7%: very likely to be exploited
Public exploit reference
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	7.5 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	5.4% (top 7%)
CISA exploited list	No
Weakness	CWE-476
Published	2026-03-24
Last modified	2026-07-14

Publisher (CNA): VulnCheck · Vendor: libvncserver project

Last updated 2026-07-14 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-03-24 18:16 UTCPublished CVE record published
2026-07-14 19:16 UTCUpdated Record last modified

libvncserver project libvncserver UPGRADE

Affected: < 0.9.15

Fixed in: 0.9.15

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy libvncserver || rpm -q libvncserver || libvncserver --version

2. UPGRADE to 0.9.15 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade libvncserver

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade libvncserver

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Exact fixes by distribution

Fedora ELN · perl-Encode · FIXED · 3.25-528.eln159 · FEDORA-2026-79991d0238 · source

sudo dnf upgrade --advisory=FEDORA-2026-79991d0238

Fedora 46 · fonttools · FIXED · 4.68.0-1.fc46 · FEDORA-2026-65d6c01c75 · source

sudo dnf upgrade --advisory=FEDORA-2026-65d6c01c75

Ubuntu 22.04 · libvncserver · FIXED · 0.9.13+dfsg-3ubuntu0.1

sudo apt update && sudo apt install --only-upgrade libvncserver dpkg --compare-versions "$(dpkg-query -W -f='${Version}' libvncserver)" ge "0.9.13+dfsg-3ubuntu0.1" && echo PATCHED || echo STILL-VULNERABLE

Ubuntu 24.04 · libvncserver · FIXED · 0.9.14+dfsg-1ubuntu0.1

sudo apt update && sudo apt install --only-upgrade libvncserver dpkg --compare-versions "$(dpkg-query -W -f='${Version}' libvncserver)" ge "0.9.14+dfsg-1ubuntu0.1" && echo PATCHED || echo STILL-VULNERABLE

Ubuntu 25.10 · libvncserver · FIXED · 0.9.15+dfsg-1ubuntu0.1

sudo apt update && sudo apt install --only-upgrade libvncserver dpkg --compare-versions "$(dpkg-query -W -f='${Version}' libvncserver)" ge "0.9.15+dfsg-1ubuntu0.1" && echo PATCHED || echo STILL-VULNERABLE

Debian 12 · libvncserver · FIXED · 0.9.14+dfsg-1+deb12u1

sudo apt update && sudo apt install --only-upgrade libvncserver dpkg --compare-versions "$(dpkg-query -W -f='${Version}' libvncserver)" ge "0.9.14+dfsg-1+deb12u1" && echo PATCHED || echo STILL-VULNERABLE

Debian 13 · libvncserver · FIXED · 0.9.15+dfsg-1+deb13u1

sudo apt update && sudo apt install --only-upgrade libvncserver dpkg --compare-versions "$(dpkg-query -W -f='${Version}' libvncserver)" ge "0.9.15+dfsg-1+deb13u1" && echo PATCHED || echo STILL-VULNERABLE

RHEL 6 · libvncserver · DEFERRED

RHEL 7 · libvncserver · NOT AFFECTED

RHEL 8 · libvncserver · DEFERRED

RHEL 9 · gnome-remote-desktop · NO FIX YET

Amazon Linux 2 · see advisory · FIXED · ALAS2-2026-3247 · source

sudo yum update --advisory=ALAS2-2026-3247

Public exploits and detection

Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.

Write-up: github.com/LibVNC/libvncserver/security/advisories/GHSA-xjp8-4qqv-5x4x

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-32854?

libvncserver: upgrade to 0.9.15. Exact commands for each OS are on this page.

Is CVE-2026-32854 being exploited?

CVE-2026-32854 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-32854 affect?

CVE-2026-32854 affects libvncserver. Severity is high (CVSS 7.5). 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 se

How urgent is CVE-2026-32854?

Priority 59/100. High severity; EPSS top 7%: very likely to be exploited; Public exploit reference; Remotely exploitable, no login, no user action

Software pages

Apache HTTP Server vulnerabilities

Related CVEs

CVE-2026-32853 HIGH 8.1 UPGRADE LibVNCServer versions 0.9.15 and prior (fixed in commit 009008e) contain a heap out-of-bounds read vulnerabili

References

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