CVE-2026-64783

HIGHPre-NVD 8.88.8
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to the CVSS score beside it.

Score 8.8 from GitHub Security Advisory (severity: HIGH) published 2026-07-27. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 8.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: CISA-ADP (Vulnrichment) CVSS v3.1, EPSS, GitHub Security Advisory
Trending — 4 sources updated this week
8.8EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines (the SSVC decision on this page).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.4%CVSS: 8.8Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

A use-after-free issue was addressed with improved memory management. This issue is fixed in Safari 26.6, iOS 26.6 and iPadOS 26.6, macOS Tahoe 26.6, visionOS 26.6, watchOS 26.6. Processing maliciously crafted web content may lead to an unexpected Safari crash.

CVSS v3
8.8
EG Score
8.8HIGHmedium confidence
EG Risk
40
EG Risk 40/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity88% × 45%
Impact severity (EG Severity): CVSS 8.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.4% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Track* at high (mission-essential systems).
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it within your standard update timelines.
EPSS PROB
0.4%
EPSS %ILE
35th
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (8.8): severity, escalated by confirmed exploitation. This CVE's 8.8 is its impact severity (EG Severity), not escalated.

EG Severity
8.8 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.4% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-17). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at low or medium mission impact; Track* at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Track* at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines.

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

July 27, 2026

Last Modified

July 28, 2026

Advisory Details (5)

Auto-updated Jul 28, 2026
Patch available.
Web page

About the security content of Safari 26.6 - Apple Support

https://support.apple.com/en-us/128073
Web page

About the security content of visionOS 26.6 - Apple Support

https://support.apple.com/en-us/128070
Web page

About the security content of watchOS 26.6 - Apple Support

https://support.apple.com/en-us/128068
Web page

About the security content of macOS Tahoe 26.6 - Apple Support

https://support.apple.com/en-us/128067
Web page

About the security content of iOS 26.6 and iPadOS 26.6 - Apple Support

https://support.apple.com/en-us/128066

Patch Availability(3)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
ubuntuwebkitgtk-webdriver (2.52.6-0ubuntu0.26.04.1) @ resolute2026-10-07ubuntu
redhatwebkit2gtk3-0:2.54.0-1.el8_102026-09-30redhat
redhatwebkit2gtk3-0:2.54.0-1.el9_82026-09-21redhat

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

(6 across 3 ecosystems)
Debian:12(2)
PackageVulnerable rangeFix by version rangeDependents
webkit2gtk2.40.1-1 ... 2.54.0-1~exp1 (167 versions)
  • every version on: no fix on record
—
wpewebkit2.38.6-1 ... 2.54.0-2 (56 versions)
  • every version on: no fix on record
—
Debian:13(2)
PackageVulnerable rangeFix by version rangeDependents
webkit2gtk2.48.3-1 ... 2.52.5-1~deb13u1 (50 versions)
  • every version up to 2.52.6-1~deb13u1: fixed in 2.52.6-1~deb13u1
—
wpewebkit2.48.3-1 ... 2.54.0-2 (22 versions)
  • every version on: no fix on record
—
Debian:14(2)
PackageVulnerable rangeFix by version rangeDependents
webkit2gtk2.48.3-1 ... 2.52.6-1~deb13u1 (51 versions)
  • every version up to 2.52.6-1: fixed in 2.52.6-1
—
wpewebkit2.48.3-1 ... 2.52.5-1 (19 versions)
  • every version up to 2.52.6-1: fixed in 2.52.6-1
—

Weakness Classification(1)

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

Additional Vendor Advisories

(1)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 11× in last 7d / 65× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

Showing the most recent 100 of 282 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 182 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  2. 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  3. 2026-10-18 03:22 UTCEG score recompute
  4. 2026-10-17 16:35 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  5. 2026-10-16 16:43 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  6. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  7. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  8. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  9. 2026-10-13 11:37 UTCEG score recompute
  10. 2026-10-13 11:37 UTCVendor advisory
  11. 2026-10-13 11:36 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  12. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  13. 2026-10-12 15:47 UTCEG score recompute
  14. 2026-10-11 19:32 UTCEG score recompute
  15. 2026-10-11 16:47 UTCEG score recompute
  16. 2026-10-11 14:08 UTCEG score recompute
  17. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  18. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  19. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  20. 2026-10-08 17:13 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  21. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  22. 2026-10-07 00:11 UTCEG score recompute
  23. 2026-10-07 00:11 UTCVendor advisory
  24. 2026-10-07 00:11 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  25. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.4% · 35th percentile
Show 75 more
  1. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  2. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  3. 2026-10-04 07:13 UTCEG score recompute
  4. 2026-10-04 07:13 UTCVendor advisory
  5. 2026-10-04 07:13 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  6. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  7. 2026-10-02 18:25 UTCEG score recompute
  8. 2026-10-02 18:25 UTCVendor advisory
  9. 2026-10-02 18:25 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  10. 2026-10-02 17:56 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  11. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  12. 2026-10-01 15:44 UTCVendor advisory
  13. 2026-10-01 15:44 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  14. 2026-10-01 03:47 UTCEG score recompute
  15. 2026-10-01 03:47 UTCVendor advisory
  16. 2026-10-01 03:46 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  17. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  18. 2026-09-29 07:49 UTCEG score recompute
  19. 2026-09-29 07:49 UTCVendor advisory
  20. 2026-09-29 07:49 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  21. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  22. 2026-09-28 03:28 UTCEG score recompute
  23. 2026-09-28 03:28 UTCVendor advisory
  24. 2026-09-28 03:28 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  25. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  26. 2026-09-25 06:32 UTCEG score recompute
  27. 2026-09-25 06:32 UTCVendor advisory
  28. 2026-09-25 06:32 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  29. 2026-09-24 09:40 UTCVendor advisory
  30. 2026-09-24 09:40 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  31. 2026-09-23 21:58 UTCEG score recompute
  32. 2026-09-23 21:58 UTCVendor advisory
  33. 2026-09-23 21:58 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  34. 2026-09-23 17:54 UTCEPSS rescoreEPSS 0.4% · 36th percentile
  35. 2026-09-23 09:26 UTCVendor advisory
  36. 2026-09-23 09:26 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  37. 2026-09-22 21:45 UTCEG score recompute
  38. 2026-09-22 21:45 UTCVendor advisory
  39. 2026-09-22 21:45 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  40. 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.4% · 36th percentile
  41. 2026-09-20 00:39 UTCEG score recompute
  42. 2026-09-20 00:39 UTCVendor advisory
  43. 2026-09-20 00:39 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  44. 2026-09-19 08:08 UTCEG score recompute
  45. 2026-09-19 08:08 UTCVendor advisory
  46. 2026-09-19 08:08 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  47. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.4% · 36th percentile
  48. 2026-09-18 18:23 UTCVendor advisory
  49. 2026-09-18 18:23 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  50. 2026-09-18 02:11 UTCEG score recompute
  51. 2026-09-18 02:11 UTCVendor advisory
  52. 2026-09-18 02:11 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  53. 2026-09-17 01:43 UTCEG score recompute
  54. 2026-09-17 01:43 UTCVendor advisory
  55. 2026-09-17 01:43 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  56. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.4% · 36th percentile
  57. 2026-09-16 05:58 UTCEG score recompute
  58. 2026-09-16 05:58 UTCVendor advisory
  59. 2026-09-16 05:58 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  60. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.4% · 36th percentile
  61. 2026-09-15 08:55 UTCEG score recompute
  62. 2026-09-15 08:55 UTCVendor advisory
  63. 2026-09-15 08:55 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  64. 2026-09-14 08:13 UTCVendor advisory
  65. 2026-09-14 08:13 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  66. 2026-09-13 20:29 UTCEG score recompute
  67. 2026-09-13 20:29 UTCVendor advisory
  68. 2026-09-13 20:29 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  69. 2026-09-13 08:03 UTCVendor advisory
  70. 2026-09-13 08:02 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  71. 2026-09-12 20:22 UTCEG score recompute
  72. 2026-09-12 20:22 UTCVendor advisory
  73. 2026-09-12 20:22 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8
  74. 2026-09-12 08:40 UTCVendor advisory
  75. 2026-09-12 08:40 UTCGHSA enrichmentGHSA-v4g2-v8g7-xcrm · GitHub severity HIGH · GitHub CVSS 8.8

Frequently asked(5)

What is CVE-2026-64783?
CVE-2026-64783 is a high-severity vulnerability; its CVE record was published on July 27, 2026. A use-after-free issue was addressed with improved memory management. This issue is fixed in Safari 26.6, iOS 26.6 and iPadOS 26.6, macOS Tahoe 26.6, visionOS 26.6, watchOS 26.6. Processing maliciously crafted web content may lead to an unexpected Safari crash.
When was the CVE record for CVE-2026-64783 published?
The CVE record for CVE-2026-64783 was published on July 27, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of July 28, 2026; the record at its source may have been updated since.
Is CVE-2026-64783 actively exploited?
CVE-2026-64783 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.4% probability of exploitation in the next 30 days (35th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-64783?
CVE-2026-64783 has a CVSS v3.1 base score of 8.8 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-64783?
A fix for CVE-2026-64783 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-64783 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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