CVE-2009-0478

NONECVSS 0.0Weaponized
0.0
EchelonGraph verdictPatch this weekExploitation is likely or a public exploit exists.
  • High exploitation likelihood — EPSS 72%
CISA-KEV: Not listedEPSS: 72%CVSS: Exploit: NoneExposed: 0

A fix is available — apply it.

Squid 2.7 to 2.7.STABLE5, 3.0 to 3.0.STABLE12, and 3.1 to 3.1.0.4 allows remote attackers to cause a denial of service via an HTTP request with an invalid version number, which triggers a reachable assertion in (1) HttpMsg.c and (2) HttpStatusLine.c.

CVSS v3
EG Score
0.0(none)
EPSS
99.4%
KEV
Not listed

Published

February 8, 2009

Last Modified

April 23, 2026

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntusquid (2.7.STABLE3-1ubuntu2.1) @ intrepid2026-05-30ubuntu

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.

All Vendor Advisories

(1)

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 / 27× 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 20:41 UTCOSV refresh
  2. 2026-07-06 16:23 UTCEPSS rescore
  3. 2026-07-05 02:26 UTCEPSS rescore
  4. 2026-07-05 02:26 UTCEPSS rescore
  5. 2026-07-04 06:27 UTCEPSS rescore
  6. 2026-07-01 15:02 UTCEPSS rescore
  7. 2026-06-28 14:03 UTCEPSS rescore
  8. 2026-06-28 04:52 UTCEPSS rescore
  9. 2026-06-28 04:52 UTCEPSS rescore
  10. 2026-06-25 13:46 UTCEPSS rescore
  11. 2026-06-25 13:46 UTCEPSS rescore
  12. 2026-06-24 14:02 UTCEPSS rescore
  13. 2026-06-24 14:02 UTCEPSS rescore
  14. 2026-06-23 21:29 UTCEPSS rescore
  15. 2026-06-23 21:29 UTCEPSS rescore
  16. 2026-06-21 14:53 UTCEPSS rescore
  17. 2026-06-21 01:56 UTCEPSS rescore
  18. 2026-06-21 01:56 UTCEPSS rescore
  19. 2026-06-19 08:25 UTCOSV refresh
  20. 2026-06-17 17:49 UTCEPSS rescore
  21. 2026-06-17 17:49 UTCEPSS rescore
  22. 2026-06-15 17:44 UTCEPSS rescore
  23. 2026-06-12 23:08 UTCEPSS rescore
  24. 2026-06-12 23:08 UTCEPSS rescore
  25. 2026-06-10 22:14 UTCEPSS rescore
Show 29 more
  1. 2026-06-10 13:17 UTCEPSS rescore
  2. 2026-06-08 14:13 UTCEPSS rescore
  3. 2026-06-07 15:22 UTCEPSS rescore
  4. 2026-06-07 15:22 UTCEPSS rescore
  5. 2026-06-06 13:44 UTCEPSS rescore
  6. 2026-06-06 13:44 UTCEPSS rescore
  7. 2026-06-06 13:44 UTCEPSS rescore
  8. 2026-06-05 22:44 UTCEPSS rescore
  9. 2026-06-05 22:44 UTCEPSS rescore
  10. 2026-06-05 06:07 UTCEPSS rescore
  11. 2026-06-01 13:49 UTCEPSS rescore
  12. 2026-06-01 13:49 UTCEPSS rescore
  13. 2026-05-31 00:13 UTCEPSS rescore
  14. 2026-05-31 00:13 UTCEPSS rescore
  15. 2026-05-30 18:22 UTCEG score recompute
  16. 2026-05-30 18:22 UTCVendor advisory
  17. 2026-05-30 18:22 UTCGHSA enrichment
  18. 2026-05-29 13:40 UTCEPSS rescore
  19. 2026-05-28 13:42 UTCEPSS rescore
  20. 2026-05-28 13:42 UTCEPSS rescore
  21. 2026-05-28 13:42 UTCEPSS rescore
  22. 2026-05-26 13:41 UTCEPSS rescore
  23. 2026-05-26 13:41 UTCEPSS rescore
  24. 2026-05-26 07:16 UTCEPSS rescore
  25. 2026-05-26 07:16 UTCEPSS rescore
  26. 2026-05-22 21:15 UTCEPSS rescore
  27. 2026-05-22 21:15 UTCEPSS rescore
  28. 2026-05-22 02:06 UTCOSV refresh
  29. 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-8021✓ verified
    First seen Feb 9, 2009

    Squid < 3.1 5 - HTTP Version Number Parsing Denial of Service

    Open source ↗

Frequently asked(4)

What is CVE-2009-0478?
CVE-2009-0478 is a none vulnerability published on February 8, 2009. Squid 2.7 to 2.7.STABLE5, 3.0 to 3.0.STABLE12, and 3.1 to 3.1.0.4 allows remote attackers to cause a denial of service via an HTTP request with an invalid version number, which triggers a reachable assertion in (1) HttpMsg.c and (2) HttpStatusLine.c.
When was CVE-2009-0478 disclosed?
CVE-2009-0478 was first published in the National Vulnerability Database on February 8, 2009, with the most recent update on April 23, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2009-0478 actively exploited?
CVE-2009-0478 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 99.4% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
How do I remediate CVE-2009-0478?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2009-0478, 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

Explore the affected products and dependency analysis for CVE-2009-0478

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