CVE-2023-4863

HIGHNVD 8.89.0▲
EchelonGraph scoreHIGH confidence

Score elevated to 9.0 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2023-09-13), indicating real-world exploitation has been confirmed by US federal agencies. NVD baseline CVSS 8.8 retained for reference. Confidence: HIGH.

Triggered by: CISA KEV (actively exploited)
Sources: cisa_kev, epss, nvd
Trending — 4 sources updated this weekExploited in the wild
8.8
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV)
CISA-KEV: ExploitedEPSS: 100%CVSS: 8.8Exploit: NoneExposed: 0

A fix is available — apply it.

Heap buffer overflow in libwebp in Google Chrome prior to 116.0.5845.187 and libwebp 1.3.2 allowed a remote attacker to perform an out of bounds memory write via a crafted HTML page. (Chromium security severity: Critical)

CVSS v3
8.8
EG Score
9.0(high)
EPSS
100.0%
KEV
⚠ Exploited

Published

September 12, 2023

Last Modified

June 17, 2026

Advisory Details (10)

Auto-updated Jun 1, 2026
⚠️ Active exploitation confirmed. No patch confirmed yet.
generic

oss-security - Re: CVE-2023-4863: libwebp: Heap buffer overflow in WebP Codec

http://www.openwall.com/lists/oss-security/2023/09/26/7
generic🔴 Active Exploitation

oss-security - Re: CVE-2023-4863: libwebp: Heap buffer overflow in WebP Codec

http://www.openwall.com/lists/oss-security/2023/09/26/1
generic

oss-security - Re: CVE-2023-4863: libwebp: Heap buffer overflow in WebP Codec

http://www.openwall.com/lists/oss-security/2023/09/22/8
generic

oss-security - Re: CVE-2023-4863: libwebp: Heap buffer overflow in WebP Codec

http://www.openwall.com/lists/oss-security/2023/09/22/7
generic

oss-security - Re: CVE-2023-4863: libwebp: Heap buffer overflow in WebP Codec

http://www.openwall.com/lists/oss-security/2023/09/22/6
generic

oss-security - Re: CVE-2023-4863: libwebp: Heap buffer overflow in WebP Codec

http://www.openwall.com/lists/oss-security/2023/09/22/5
generic

oss-security - Re: CVE-2023-4863: libwebp: Heap buffer overflow in WebP Codec

http://www.openwall.com/lists/oss-security/2023/09/22/4
generic

oss-security - Re: CVE-2023-4863: libwebp: Heap buffer overflow in WebP Codec

http://www.openwall.com/lists/oss-security/2023/09/22/3
generic

oss-security - Re: CVE-2023-4863: libwebp: Heap buffer overflow in WebP Codec

http://www.openwall.com/lists/oss-security/2023/09/22/1
generic🔴 Active Exploitation

oss-security - CVE-2023-4863: libwebp: Heap buffer overflow in WebP Codec

http://www.openwall.com/lists/oss-security/2023/09/21/4

Patch Availability(29)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntuxul-ext-lightning (1:102.15.1+build1-0ubuntu0.20.04.1) @ focal2026-07-11ubuntu
ubuntuwebp (0.6.1-2ubuntu0.18.04.2+esm1) @ bionic2026-07-11ubuntu
ubuntuwebp (1.2.4-0.1ubuntu0.23.04.2) @ lunar2026-07-11ubuntu
ubuntufirefox-mozsymbols (117.0.1+build2-0ubuntu0.20.04.1) @ focal2026-07-11ubuntu
redhatrhel9/firefox-flatpak:flatpak-9020020231006113910.22023-10-23redhat
redhatrhel9/thunderbird-flatpak:flatpak-9020020231006114109.12023-10-23redhat
redhatlibwebp-0:1.0.0-8.el8_8.12023-09-20redhat
redhatthunderbird-0:102.15.1-1.el9_02023-09-19redhat
redhatlibwebp-0:1.0.0-5.2.el8_1.12023-09-19redhat
redhatthunderbird-0:102.15.1-1.el9_22023-09-19redhat
redhatlibwebp-0:1.2.0-7.el9_22023-09-19redhat
redhatlibwebp-0:1.0.0-7.el8_4.12023-09-19redhat
redhatlibwebp-0:1.2.0-6.el9_02023-09-18redhat
redhatlibwebp-0:1.0.0-7.el8_2.12023-09-18redhat
redhatfirefox-0:102.15.1-1.el8_22023-09-18redhat
redhatthunderbird-0:102.15.1-1.el8_82023-09-18redhat
redhatfirefox-0:102.15.1-1.el8_12023-09-18redhat
redhatthunderbird-0:102.15.1-1.el8_22023-09-18redhat
redhatthunderbird-0:102.15.1-1.el8_42023-09-18redhat
redhatfirefox-0:102.15.1-1.el9_02023-09-18redhat
redhatfirefox-0:102.15.1-1.el8_62023-09-18redhat
redhatfirefox-0:102.15.1-1.el7_92023-09-18redhat
redhatthunderbird-0:102.15.1-1.el7_92023-09-18redhat
redhatfirefox-0:102.15.1-1.el8_82023-09-18redhat
redhatfirefox-0:102.15.1-1.el9_22023-09-18redhat
redhatthunderbird-0:102.15.1-1.el8_12023-09-18redhat
redhatfirefox-0:102.15.1-1.el8_42023-09-18redhat
redhatlibwebp-0:1.0.0-7.el8_6.12023-09-18redhat
redhatthunderbird-0:102.15.1-1.el8_62023-09-18redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(13 across 5 ecosystems)
NuGet(7)
PackageVulnerable rangeFixed inDependents
magick.net-q16-anycpu10.0.0 ... 9.1.2 (184 versions)13.3.0—
magick.net-q16-hdri-anycpu10.0.0 ... 9.1.2 (181 versions)13.3.0—
magick.net-q16-x6410.0.0 ... 9.1.2 (200 versions)13.3.0—
magick.net-q8-anycpu10.0.0 ... 9.1.2 (184 versions)13.3.0—
magick.net-q8-openmp-x6410.0.0 ... 9.1.2 (81 versions)13.3.0—
magick.net-q8-x6410.0.0 ... 9.1.2 (200 versions)13.3.0—
SkiaSharp2.80.0 ... 2.88.5 (11 versions)2.88.6—
crates.io(3)
PackageVulnerable rangeFixed inDependents
libwebp-sys—0.9.3—
libwebp-sys2—0.1.8—
webp—0.2.6—
Go(1)
PackageVulnerable rangeFixed inDependents
github.com/chai2010/webp—1.1.2-0.20250406010349-76805d5a8860—
npm(1)
PackageVulnerable rangeFixed inDependents
electron—27.0.0-beta.2—
PyPI(1)
PackageVulnerable rangeFixed inDependents
pillow1.0 ... 9.5.0 (93 versions)10.0.1—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

All Vendor Advisories

(25)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 95× in last 7d / 402× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 573 total refreshes for this CVE.

  1. 2026-07-11 22:28 UTCEG score recompute
  2. 2026-07-11 22:28 UTCVendor advisory
  3. 2026-07-11 18:43 UTCEG score recompute
  4. 2026-07-11 18:43 UTCVendor advisory
  5. 2026-07-11 14:58 UTCEG score recompute
  6. 2026-07-11 14:58 UTCVendor advisory
  7. 2026-07-11 11:12 UTCEG score recompute
  8. 2026-07-11 11:12 UTCVendor advisory
  9. 2026-07-11 07:27 UTCEG score recompute
  10. 2026-07-11 07:27 UTCVendor advisory
  11. 2026-07-11 03:42 UTCEG score recompute
  12. 2026-07-11 03:42 UTCVendor advisory
  13. 2026-07-10 23:57 UTCEG score recompute
  14. 2026-07-10 23:57 UTCVendor advisory
  15. 2026-07-10 20:12 UTCEG score recompute
  16. 2026-07-10 20:12 UTCVendor advisory
  17. 2026-07-10 17:52 UTCCISA KEV update
  18. 2026-07-10 16:27 UTCEG score recompute
  19. 2026-07-10 16:27 UTCVendor advisory
  20. 2026-07-10 12:42 UTCEG score recompute
  21. 2026-07-10 12:42 UTCVendor advisory
  22. 2026-07-10 08:56 UTCEG score recompute
  23. 2026-07-10 08:56 UTCVendor advisory
  24. 2026-07-10 05:11 UTCEG score recompute
  25. 2026-07-10 05:11 UTCVendor advisory
Show 75 more
  1. 2026-07-10 01:25 UTCEG score recompute
  2. 2026-07-10 01:25 UTCVendor advisory
  3. 2026-07-09 21:38 UTCEG score recompute
  4. 2026-07-09 21:38 UTCVendor advisory
  5. 2026-07-09 17:53 UTCEG score recompute
  6. 2026-07-09 17:53 UTCVendor advisory
  7. 2026-07-09 14:07 UTCEG score recompute
  8. 2026-07-09 14:07 UTCVendor advisory
  9. 2026-07-09 10:22 UTCEG score recompute
  10. 2026-07-09 10:22 UTCVendor advisory
  11. 2026-07-09 06:37 UTCEG score recompute
  12. 2026-07-09 06:37 UTCVendor advisory
  13. 2026-07-09 02:51 UTCEG score recompute
  14. 2026-07-09 02:51 UTCVendor advisory
  15. 2026-07-08 23:06 UTCEG score recompute
  16. 2026-07-08 23:06 UTCVendor advisory
  17. 2026-07-08 19:20 UTCEG score recompute
  18. 2026-07-08 19:20 UTCVendor advisory
  19. 2026-07-08 15:34 UTCEG score recompute
  20. 2026-07-08 15:34 UTCVendor advisory
  21. 2026-07-08 11:47 UTCEG score recompute
  22. 2026-07-08 11:47 UTCVendor advisory
  23. 2026-07-08 08:00 UTCEG score recompute
  24. 2026-07-08 08:00 UTCVendor advisory
  25. 2026-07-08 04:15 UTCEG score recompute
  26. 2026-07-08 04:15 UTCVendor advisory
  27. 2026-07-08 00:28 UTCEG score recompute
  28. 2026-07-08 00:28 UTCVendor advisory
  29. 2026-07-07 20:43 UTCEG score recompute
  30. 2026-07-07 20:43 UTCVendor advisory
  31. 2026-07-07 19:01 UTCCISA KEV update
  32. 2026-07-07 17:16 UTCCISA KEV update
  33. 2026-07-07 16:57 UTCEG score recompute
  34. 2026-07-07 16:57 UTCVendor advisory
  35. 2026-07-07 13:12 UTCEG score recompute
  36. 2026-07-07 13:12 UTCVendor advisory
  37. 2026-07-07 09:26 UTCEG score recompute
  38. 2026-07-07 09:26 UTCVendor advisory
  39. 2026-07-07 05:41 UTCEG score recompute
  40. 2026-07-07 05:41 UTCVendor advisory
  41. 2026-07-07 01:53 UTCEG score recompute
  42. 2026-07-07 01:53 UTCVendor advisory
  43. 2026-07-06 22:07 UTCEG score recompute
  44. 2026-07-06 22:07 UTCVendor advisory
  45. 2026-07-06 18:21 UTCEG score recompute
  46. 2026-07-06 18:21 UTCVendor advisory
  47. 2026-07-06 16:26 UTCEPSS rescore
  48. 2026-07-06 16:26 UTCEPSS rescore
  49. 2026-07-06 14:35 UTCEG score recompute
  50. 2026-07-06 14:35 UTCVendor advisory
  51. 2026-07-06 10:49 UTCEG score recompute
  52. 2026-07-06 10:49 UTCVendor advisory
  53. 2026-07-06 07:04 UTCEG score recompute
  54. 2026-07-06 07:04 UTCVendor advisory
  55. 2026-07-06 03:17 UTCEG score recompute
  56. 2026-07-06 03:17 UTCVendor advisory
  57. 2026-07-05 23:31 UTCEG score recompute
  58. 2026-07-05 23:31 UTCVendor advisory
  59. 2026-07-05 19:46 UTCEG score recompute
  60. 2026-07-05 19:46 UTCVendor advisory
  61. 2026-07-05 16:01 UTCEG score recompute
  62. 2026-07-05 16:01 UTCVendor advisory
  63. 2026-07-05 12:16 UTCEG score recompute
  64. 2026-07-05 12:16 UTCVendor advisory
  65. 2026-07-05 08:31 UTCEG score recompute
  66. 2026-07-05 08:31 UTCVendor advisory
  67. 2026-07-05 04:45 UTCEG score recompute
  68. 2026-07-05 04:45 UTCVendor advisory
  69. 2026-07-05 00:59 UTCEG score recompute
  70. 2026-07-05 00:59 UTCVendor advisory
  71. 2026-07-04 21:12 UTCEG score recompute
  72. 2026-07-04 21:12 UTCVendor advisory
  73. 2026-07-04 17:27 UTCEG score recompute
  74. 2026-07-04 17:27 UTCVendor advisory
  75. 2026-07-04 13:41 UTCEG score recompute

Publicly available exploits

(10 references)

Working exploit code is in the public domain (10 GitHub PoCs). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • GitHub PoCShcesama/cve-2023-4863-analysis
    First seen Jun 3, 2026
    Open source ↗
  • GitHub PoCcaoweiquan322/NotEnough
    First seen Dec 19, 2023

    This tool calculates tricky canonical huffman histogram for CVE-2023-4863.

    Open source ↗
  • GitHub PoCLiveOverflow/webp-CVE-2023-4863
    First seen Dec 18, 2023
    Open source ↗
  • GitHub PoChuiwen-yayaya/CVE-2023-4863
    First seen Nov 11, 2023
    Open source ↗
  • GitHub PoCmurphysecurity/libwebp-checker
    First seen Oct 5, 2023

    A tool for finding vulnerable libwebp(CVE-2023-4863)

    Open source ↗
  • GitHub PoCGTGalaxi/ElectronVulnerableVersion
    First seen Sep 30, 2023

    Find Electron Apps Vulnerable to CVE-2023-4863 / CVE-2023-5129

    Open source ↗
  • GitHub PoCOITApps/Find-VulnerableElectronVersion
    First seen Sep 29, 2023

    Scans an executable and determines if it was wrapped in an Electron version vulnerable to the Chromium vulnerability CVE-2023-4863/ CVE-2023-5129

    Open source ↗
  • GitHub PoCtalbeerysec/BAD-WEBP-CVE-2023-4863
    First seen Sep 25, 2023

    BAD-WEBP-CVE-2023-4863

    Open source ↗
  • GitHub PoCbbaranoff/CVE-2023-4863
    First seen Sep 25, 2023
    Open source ↗
  • GitHub PoCmistymntncop/CVE-2023-4863
    First seen Sep 21, 2023
    Open source ↗

Frequently asked(6)

What is CVE-2023-4863?
CVE-2023-4863 is a high vulnerability published on September 12, 2023. Heap buffer overflow in libwebp in Google Chrome prior to 116.0.5845.187 and libwebp 1.3.2 allowed a remote attacker to perform an out of bounds memory write via a crafted HTML page. (Chromium security severity: Critical)
When was CVE-2023-4863 disclosed?
CVE-2023-4863 was first published in the National Vulnerability Database on September 12, 2023, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2023-4863 actively exploited?
Yes. CISA added CVE-2023-4863 to the Known Exploited Vulnerabilities catalog on September 13, 2023, affecting Google Chromium WebP. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate patching attention.
What is the CVSS score of CVE-2023-4863?
CVE-2023-4863 has a CVSS v3 base score of 8.8 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.0.
Which products are affected by CVE-2023-4863?
CVE-2023-4863 affects Google Chromium WebP. The full affected-products list, including version ranges and fixed versions, is shown in the Affected Packages section of this page.
How do I remediate CVE-2023-4863?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2023-4863, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2023-4863

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