CVE-2006-4020

NONECVSS 0.0Weaponized
0.0
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • No confirmed exploitation signals yet
CISA-KEV: Not listedEPSS: 2%CVSS: —Exploit: NoneExposed: 0

A fix is available — apply it.

scanf.c in PHP 5.1.4 and earlier, and 4.4.3 and earlier, allows context-dependent attackers to execute arbitrary code via a sscanf PHP function call that performs argument swapping, which increments an index past the end of an array and triggers a buffer over-read.

CVSS v3
—
EG Score
0.0(none)
EPSS
78.6%
KEV
Not listed

Published

August 8, 2006

Last Modified

April 16, 2026

References (78)

Patch Availability(5)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntuphp5-curl (5.1.2-1ubuntu3.2) @ dapper2026-05-31ubuntu
redhatpatch2006-12-11redhat
redhatphp-0:5.1.4-1.el4s1.42006-10-05redhat
redhatphp-0:4.3.9-3.182006-09-21redhat
redhatpatch2006-09-21redhat

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.

All Vendor Advisories

(5)

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 6× in last 7d / 30× 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. 2026-07-13 22:25 UTCEPSS rescore
  2. 2026-07-13 06:07 UTCEPSS rescore
  3. 2026-07-13 06:07 UTCEPSS rescore
  4. 2026-07-11 08:22 UTCEPSS rescore
  5. 2026-07-09 19:03 UTCEPSS rescore
  6. 2026-07-08 15:09 UTCEPSS rescore
  7. 2026-07-06 02:19 UTCEPSS rescore
  8. 2026-07-06 02:19 UTCEPSS rescore
  9. 2026-07-04 06:26 UTCEPSS rescore
  10. 2026-07-02 14:00 UTCEPSS rescore
  11. 2026-07-01 15:01 UTCEPSS rescore
  12. 2026-06-29 14:02 UTCEPSS rescore
  13. 2026-06-29 14:02 UTCEPSS rescore
  14. 2026-06-27 03:04 UTCEPSS rescore
  15. 2026-06-25 13:46 UTCEPSS rescore
  16. 2026-06-24 14:01 UTCEPSS rescore
  17. 2026-06-24 14:01 UTCEPSS rescore
  18. 2026-06-23 21:29 UTCEPSS rescore
  19. 2026-06-23 21:29 UTCEPSS rescore
  20. 2026-06-22 14:22 UTCEPSS rescore
  21. 2026-06-21 01:56 UTCEPSS rescore
  22. 2026-06-19 19:22 UTCEPSS rescore
  23. 2026-06-19 19:22 UTCEPSS rescore
  24. 2026-06-18 17:49 UTCEPSS rescore
  25. 2026-06-18 17:49 UTCEPSS rescore
Show 42 more
  1. 2026-06-17 17:49 UTCEPSS rescore
  2. 2026-06-17 17:49 UTCEPSS rescore
  3. 2026-06-16 17:49 UTCEPSS rescore
  4. 2026-06-16 17:49 UTCEPSS rescore
  5. 2026-06-15 17:44 UTCEPSS rescore
  6. 2026-06-13 22:56 UTCEPSS rescore
  7. 2026-06-12 23:08 UTCEPSS rescore
  8. 2026-06-11 13:55 UTCEPSS rescore
  9. 2026-06-10 22:14 UTCEPSS rescore
  10. 2026-06-10 13:17 UTCEPSS rescore
  11. 2026-06-07 15:21 UTCEPSS rescore
  12. 2026-06-05 22:43 UTCEPSS rescore
  13. 2026-06-04 13:09 UTCEPSS rescore
  14. 2026-06-04 13:09 UTCEPSS rescore
  15. 2026-06-02 20:10 UTCEPSS rescore
  16. 2026-06-02 20:10 UTCEPSS rescore
  17. 2026-06-01 13:49 UTCEPSS rescore
  18. 2026-06-01 13:49 UTCEPSS rescore
  19. 2026-06-01 13:49 UTCEPSS rescore
  20. 2026-05-31 22:28 UTCEPSS rescore
  21. 2026-05-31 07:21 UTCEG score recompute
  22. 2026-05-31 07:21 UTCVendor advisory
  23. 2026-05-31 07:21 UTCGHSA enrichment
  24. 2026-05-31 00:13 UTCEPSS rescore
  25. 2026-05-31 00:13 UTCEPSS rescore
  26. 2026-05-31 00:13 UTCEPSS rescore
  27. 2026-05-29 13:40 UTCEPSS rescore
  28. 2026-05-28 13:42 UTCEPSS rescore
  29. 2026-05-28 13:42 UTCEPSS rescore
  30. 2026-05-27 13:37 UTCEPSS rescore
  31. 2026-05-27 13:37 UTCEPSS rescore
  32. 2026-05-26 13:41 UTCEPSS rescore
  33. 2026-05-26 13:41 UTCEPSS rescore
  34. 2026-05-24 16:42 UTCEPSS rescore
  35. 2026-05-22 21:15 UTCEPSS rescore
  36. 2026-05-22 21:15 UTCEPSS rescore
  37. 2026-05-21 22:38 UTCEPSS rescore
  38. 2026-05-20 22:36 UTCEPSS rescore
  39. 2026-05-20 22:36 UTCEPSS rescore
  40. 2026-05-20 11:20 UTCEPSS rescore
  41. 2026-05-20 11:20 UTCEPSS rescore
  42. 2026-05-18 21:29 UTCEPSS rescore

Publicly available exploits

(1 reference)

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

  • Exploit-DBEDB-2193✓ verified
    First seen Aug 16, 2006

    PHP 4.4.3/5.1.4 - 'sscanf' Local Buffer Overflow

    Open source ↗

Frequently asked(4)

What is CVE-2006-4020?
CVE-2006-4020 is a none vulnerability published on August 8, 2006. scanf.c in PHP 5.1.4 and earlier, and 4.4.3 and earlier, allows context-dependent attackers to execute arbitrary code via a sscanf PHP function call that performs argument swapping, which increments an index past the end of an array and triggers a buffer over-read.
When was CVE-2006-4020 disclosed?
CVE-2006-4020 was first published in the National Vulnerability Database on August 8, 2006, with the most recent update on April 16, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2006-4020 actively exploited?
CVE-2006-4020 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 78.6% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
How do I remediate CVE-2006-4020?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2006-4020, 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.

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