CVE-2023-4863

CRITICALNVD 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
9.0EG
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV)
CISA-KEV: ExploitedEPSS PROB: 100%CVSS: 8.8Exploit: cisa kev · ssvc active · epss top5pct · epss high · public exploitExposed: 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)
EG Risk
81(Attend)
EG Risk 81/100SSVC: Attend

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity90% × 45%
Exploitation100% × 40%
Automatability0% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
100%
EPSS %ILE
100%
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
ubuntuwebp (1.2.4-0.1ubuntu0.23.04.2) @ lunar2026-07-27ubuntu
ubuntuwebp (0.6.1-2ubuntu0.18.04.2+esm1) @ bionic2026-07-27ubuntu
ubuntuxul-ext-lightning (1:102.15.1+build1-0ubuntu0.23.04.1) @ lunar2026-07-27ubuntu
ubuntufirefox-mozsymbols (117.0.1+build2-0ubuntu0.20.04.1) @ focal2026-07-27ubuntu
redhatrhel9/thunderbird-flatpak:flatpak-9020020231006114109.12023-10-23redhat
redhatrhel9/firefox-flatpak:flatpak-9020020231006113910.22023-10-23redhat
redhatlibwebp-0:1.0.0-8.el8_8.12023-09-20redhat
redhatthunderbird-0:102.15.1-1.el9_22023-09-19redhat
redhatlibwebp-0:1.2.0-7.el9_22023-09-19redhat
redhatthunderbird-0:102.15.1-1.el9_02023-09-19redhat
redhatlibwebp-0:1.0.0-7.el8_4.12023-09-19redhat
redhatlibwebp-0:1.0.0-5.2.el8_1.12023-09-19redhat
redhatlibwebp-0:1.2.0-6.el9_02023-09-18redhat
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.el8_82023-09-18redhat
redhatlibwebp-0:1.0.0-7.el8_2.12023-09-18redhat
redhatfirefox-0:102.15.1-1.el8_22023-09-18redhat
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
redhatfirefox-0:102.15.1-1.el9_02023-09-18redhat
redhatfirefox-0:102.15.1-1.el7_92023-09-18redhat
redhatfirefox-0:102.15.1-1.el8_62023-09-18redhat
redhatthunderbird-0:102.15.1-1.el7_92023-09-18redhat

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 41× in last 7d / 207× 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 415 total refreshes for this CVE.

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

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 ↗

Related CVEs(same vendor + same CWE)

Frequently asked(6)

What is CVE-2023-4863?
CVE-2023-4863 is a critical 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

Explore →

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