CVE-2018-4121

HIGHNVD 8.88.8—
EchelonGraph scoreMEDIUM confidence

Score 8.8 from GitHub Security Advisory (severity: HIGH) published 2022-05-14. NVD baseline CVSS 8.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Weaponized
8.8
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 13%CVSS: 8.8Exploit: NoneExposed: 0

A fix is available — apply it.

An issue was discovered in certain Apple products. iOS before 11.3 is affected. Safari before 11.1 is affected. iCloud before 7.4 on Windows is affected. iTunes before 12.7.4 on Windows is affected. tvOS before 11.3 is affected. watchOS before 4.3 is affected. The issue involves the "WebKit" component. It allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption and application crash) via a crafted web site.

CVSS v3
8.8
EG Score
8.8(medium)
EPSS
95.9%
KEV
Not listed

Published

April 3, 2018

Last Modified

November 21, 2024

References (20)

Vendor Advisories for CVE-2018-4121(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatzenity-0:3.28.1-1.el72018-10-30redhat

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.

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 13× in last 7d / 42× 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.

  1. 2026-07-07 13:42 UTCEPSS rescore
  2. 2026-07-07 13:42 UTCEPSS rescore
  3. 2026-07-06 16:25 UTCEPSS rescore
  4. 2026-07-06 16:24 UTCEPSS rescore
  5. 2026-07-06 02:20 UTCEPSS rescore
  6. 2026-07-05 02:27 UTCEPSS rescore
  7. 2026-07-04 10:56 UTCOSV refresh
  8. 2026-07-04 06:28 UTCEPSS rescore
  9. 2026-07-04 06:28 UTCEPSS rescore
  10. 2026-07-01 15:03 UTCEPSS rescore
  11. 2026-07-01 15:03 UTCEPSS rescore
  12. 2026-06-30 23:20 UTCEPSS rescore
  13. 2026-06-30 23:20 UTCEPSS rescore
  14. 2026-06-29 14:03 UTCEPSS rescore
  15. 2026-06-28 14:04 UTCEPSS rescore
  16. 2026-06-28 04:53 UTCEPSS rescore
  17. 2026-06-28 04:53 UTCEPSS rescore
  18. 2026-06-27 03:06 UTCEPSS rescore
  19. 2026-06-27 03:06 UTCEPSS rescore
  20. 2026-06-25 13:47 UTCEPSS rescore
  21. 2026-06-25 13:47 UTCEPSS rescore
  22. 2026-06-24 14:02 UTCEPSS rescore
  23. 2026-06-24 14:02 UTCEPSS rescore
  24. 2026-06-23 21:30 UTCEPSS rescore
  25. 2026-06-23 21:30 UTCEPSS rescore
Show 40 more
  1. 2026-06-21 01:57 UTCEPSS rescore
  2. 2026-06-21 01:57 UTCEPSS rescore
  3. 2026-06-19 19:23 UTCEPSS rescore
  4. 2026-06-19 19:23 UTCEPSS rescore
  5. 2026-06-18 17:50 UTCEPSS rescore
  6. 2026-06-18 17:50 UTCEPSS rescore
  7. 2026-06-17 17:50 UTCEPSS rescore
  8. 2026-06-16 17:50 UTCEPSS rescore
  9. 2026-06-16 17:50 UTCEPSS rescore
  10. 2026-06-15 22:39 UTCOSV refresh
  11. 2026-06-15 17:45 UTCEPSS rescore
  12. 2026-06-13 22:58 UTCEPSS rescore
  13. 2026-06-12 23:09 UTCEPSS rescore
  14. 2026-06-12 23:09 UTCEPSS rescore
  15. 2026-06-11 13:57 UTCEPSS rescore
  16. 2026-06-10 22:16 UTCEPSS rescore
  17. 2026-06-10 13:19 UTCEPSS rescore
  18. 2026-06-07 15:22 UTCEPSS rescore
  19. 2026-06-07 15:22 UTCEPSS rescore
  20. 2026-06-06 13:45 UTCEPSS rescore
  21. 2026-06-06 13:45 UTCEPSS rescore
  22. 2026-06-05 22:45 UTCEPSS rescore
  23. 2026-06-05 22:45 UTCEPSS rescore
  24. 2026-06-05 06:08 UTCEPSS rescore
  25. 2026-06-05 06:08 UTCEPSS rescore
  26. 2026-06-04 13:10 UTCEPSS rescore
  27. 2026-06-02 20:11 UTCEPSS rescore
  28. 2026-06-02 20:11 UTCEPSS rescore
  29. 2026-06-01 13:50 UTCEPSS rescore
  30. 2026-06-01 13:50 UTCEPSS rescore
  31. 2026-05-31 22:29 UTCEPSS rescore
  32. 2026-05-31 00:14 UTCEPSS rescore
  33. 2026-05-31 00:14 UTCEPSS rescore
  34. 2026-05-29 13:41 UTCEPSS rescore
  35. 2026-05-28 13:42 UTCEPSS rescore
  36. 2026-05-28 13:42 UTCEPSS rescore
  37. 2026-05-28 09:45 UTCEG score recompute
  38. 2026-05-28 09:45 UTCVendor advisory
  39. 2026-05-28 09:45 UTCGHSA enrichment
  40. 2026-05-23 19:35 UTCOSV refresh

Publicly available exploits

(2 references)

Working exploit code is in the public domain (1 GitHub PoC) (1 Exploit-DB entry). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • GitHub PoCFSecureLABS/CVE-2018-4121
    First seen Apr 19, 2018

    macOS 10.13.3 (17D47) Safari Wasm Exploit

    Open source ↗
  • Exploit-DBEDB-44427✓ verified
    First seen Apr 9, 2018

    WebKit - WebAssembly Parsing Does not Correctly Check Section Order

    Open source ↗

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2018-4121?
CVE-2018-4121 is a high vulnerability published on April 3, 2018. An issue was discovered in certain Apple products. iOS before 11.3 is affected. Safari before 11.1 is affected. iCloud before 7.4 on Windows is affected. iTunes before 12.7.4 on Windows is affected. tvOS before 11.3 is affected. watchOS before 4.3 is affected. The issue involves the "WebKit"…
When was CVE-2018-4121 disclosed?
CVE-2018-4121 was first published in the National Vulnerability Database on April 3, 2018, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2018-4121 actively exploited?
CVE-2018-4121 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 95.9% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2018-4121?
CVE-2018-4121 has a CVSS v3 base score of 8.8 (NVD).
How do I remediate CVE-2018-4121?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2018-4121, 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

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