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CriticalVulnerabilityCVE-2023-4863updated 27 Oct 2026, 16:19 UTC

libwebp flaw lets crafted images corrupt memory in many apps

A flaw in the image library libwebp lets a specially crafted image overwrite computer memory. Attackers can use this to run their own code on the affected program or system.

Fix availableOfficial, 2 sources
SeverityCriticalCVSS 8.8 of 10
Being exploited?UnclearNo reports either way yet
Fix available?Yesrust/libwebp-sys2 0.1.8; rust/libwebp-sys 0.9.3; rust/webp 0.2.6; electron 22.3.24, 24.8.3, 25.8.1, 26.2.1, 27.0.0-beta.2; SkiaSharp 2.88.6; Pillow 10.0.1; Magick.NET 13.3.0; GENESIS64 and ICONICS Suite 10.97.3 or later · since 27 Oct 2026
How sure is this?Official, 2 sourcesBacked by an official source

How the attack works simplified

  1. 1Attacker crafts imageMalicious WebP file or HTML page
  2. 2Victim opens itApp or browser decodes the image
  3. 3libwebp overflows heapOut-of-bounds write corrupts memory
  4. 4Code runsAttacker gains control of the process
  5. ResultAttacker runs code or crashes the app

What happened

A heap buffer overflow in libwebp (CVE-2023-4863) causes an out-of-bounds memory write when processing a crafted WebP image or HTML page, affecting libwebp and the many packages that bundle it.

Why it is dangerous: A successful attack can run arbitrary code, leak or destroy data, or crash the system. Anyone whose software decodes WebP images, including desktop apps built on Electron and imaging libraries, is at risk.

Are you affected?

You are affected if you use Electron 22-27 beta builds before the listed fixes, Pillow before 10.0.1, SkiaSharp 2.x before 2.88.6, Magick.NET before 13.3.0, or Rust crates libwebp-sys/webp before the fixed versions.

Package / productAffected versionsFixed in
libwebp-sys2 · rust< 0.1.80.1.8
libwebp-sys · rust< 0.9.30.9.3
electron · npm>= 22.0.0, < 22.3.2422.3.24
electron · npm>= 24.0.0, < 24.8.324.8.3
electron · npm>= 25.0.0, < 25.8.125.8.1
electron · npm>= 26.0.0, < 26.2.126.2.1
electron · npm>= 27.0.0-beta.1, < 27.0.0-beta.227.0.0-beta.2
SkiaSharp · nuget>= 2.0.0, < 2.88.62.88.6
Pillow · pip< 10.0.110.0.1
webp · rust< 0.2.60.2.6
magick.net-q16-anycpu · nuget< 13.3.013.3.0
magick.net-q16-hdri-anycpu · nuget< 13.3.013.3.0
magick.net-q16-x64 · nuget< 13.3.013.3.0
magick.net-q8-anycpu · nuget< 13.3.013.3.0
magick.net-q8-openmp-x64 · nuget< 13.3.013.3.0
magick.net-q8-x64 · nuget< 13.3.013.3.0
github.com/chai2010/webp · go< 0.0.0-20250406010349-76805d5a88600.0.0-20250406010349-76805d5a8860
github.com/chai2010/webp · go>= 1.1.2, < 1.4.01.4.0
github.com/chai2010/webp · go>= 0.0.0, < 1.1.2-0.20250406010349-76805d5a88601.1.2-0.20250406010349-76805d5a8860

What to do

  1. Update Electron, Pillow, SkiaSharp, Magick.NET and Rust libwebp crates to the fixed versions listed
  2. For Mitsubishi Electric GENESIS64 or ICONICS Suite, install version 10.97.3 or later from the vendor download page
  3. Rebuild and redeploy any application that bundles libwebp, then verify the dependency versions

Timeline

  1. 12 Sept 2023, 15:30 UTC
    Publicly disclosed
  2. 27 Oct 2026, 12:00 UTC
    Reported by CISA · CISA
  3. 27 Oct 2026, 16:10 UTC
    Picked up by Zero Radar
  4. 27 Oct 2026, 16:19 UTC
    GitHub Advisory reported on it · GitHub Advisory
  5. 27 Oct 2026, 16:19 UTC
    Fixed version published: libwebp-sys2 0.1.8, libwebp-sys 0.9.3, electron 22.3.24 · GitHub Advisory

Sources 2 reports, oldest first

Official vendor, government CERT or advisory database

Technical details

ID
CVE-2023-4863 · GHSA-j7hp-h8jx-5ppr
CVSS
8.8 / 10
EPSS
100% chance of exploitation within 30 days
Disclosed
12 Sept 2023, 15:30 UTC
On Zero Radar
27 Oct 2026, 16:10 UTC (1141 days after disclosure)
Last change
27 Oct 2026, 16:19 UTC

The plain-language parts and the attack diagram were written by an AI model (anthropic/claude-haiku-5.5) from the sources above. Facts like versions, exploitation and dates come from the sources themselves. How Zero Radar works

libwebp flaw lets crafted images corrupt memory in many apps · Zero Radar