CVE-2011-4858

NONECVSS 0.0Weaponized
0.0
EchelonGraph verdictPatch this weekExploitation is likely or a public exploit exists.
  • 61 internet-exposed hosts are running an affected version right now
  • High exploitation likelihood — EPSS 80%
CISA-KEV: Not listedEPSS: 80%CVSS: Exploit: NoneExposed: 61

A fix is available — apply it.

Apache Tomcat before 5.5.35, 6.x before 6.0.35, and 7.x before 7.0.23 computes hash values for form parameters without restricting the ability to trigger hash collisions predictably, which allows remote attackers to cause a denial of service (CPU consumption) by sending many crafted parameters.

Live · internet exposure

61 internet-exposed hosts are running an affected version of CVE-2011-4858 right now.

across 18 countries (United States, China, United Kingdom, Singapore, Indonesia)top: tomcat
See the live KEV-Exposure radar →Found passively from public internet-scan data — aggregate, host-redacted.

EchelonGraph is the only CVE feed that fuses live vulnerability intelligence with its own live internet-exposure radar — so you see not just that a CVE is exploited, but how much of the internet is exposed to it right now.

CVSS v3
EG Score
0.0(none)
EPSS
99.6%
KEV
Not listed

Published

January 5, 2012

Last Modified

April 29, 2026

Patch Availability(16)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulibtomcat6-java (6.0.28-10ubuntu2.3) @ natty2026-05-29ubuntu
redhattomcat5-0:5.5.33-28_patch_07.ep5.el62012-05-21redhat
redhattomcat6-0:6.0.32-24_patch_07.ep5.el62012-05-21redhat
redhatpatch2012-05-21redhat
redhatpatch2012-05-21redhat
redhattomcat5-0:5.5.23-0jpp.31.el5_82012-04-11redhat
redhattomcat6-0:6.0.24-36.el6_22012-04-11redhat
redhatpatch2012-03-20redhat
redhatpatch2012-02-22redhat
redhatpatch2012-02-02redhat
redhatpatch2012-02-01redhat
redhatjbossweb-0:2.1.12-3_patch_03.2.ep5.el62012-01-31redhat
redhatpatch2012-01-31redhat
redhatpatch2012-01-31redhat
redhatpatch2012-01-31redhat
redhatpatch2012-01-19redhat

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

(1 across 1 ecosystem)
Maven(1)
PackageVulnerable rangeFixed inDependents
org.apache.tomcat:tomcat7.0.23

All Vendor Advisories

(17)

Data Freshness Timeline

(refreshed 4× in last 7d / 22× 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. 2026-07-04 06:27 UTCEPSS rescore
  2. 2026-07-01 15:02 UTCEPSS rescore
  3. 2026-06-30 23:19 UTCEPSS rescore
  4. 2026-06-30 23:19 UTCEPSS rescore
  5. 2026-06-25 13:46 UTCEPSS rescore
  6. 2026-06-25 13:46 UTCEPSS rescore
  7. 2026-06-23 21:30 UTCEPSS rescore
  8. 2026-06-21 14:53 UTCEPSS rescore
  9. 2026-06-21 01:56 UTCEPSS rescore
  10. 2026-06-21 01:56 UTCEPSS rescore
  11. 2026-06-16 17:49 UTCEPSS rescore
  12. 2026-06-16 17:49 UTCEPSS rescore
  13. 2026-06-15 17:44 UTCEPSS rescore
  14. 2026-06-14 23:14 UTCEPSS rescore
  15. 2026-06-14 23:14 UTCEPSS rescore
  16. 2026-06-13 22:57 UTCEPSS rescore
  17. 2026-06-12 23:08 UTCEPSS rescore
  18. 2026-06-11 13:56 UTCEPSS rescore
  19. 2026-06-10 22:14 UTCEPSS rescore
  20. 2026-06-10 13:18 UTCEPSS rescore
  21. 2026-06-08 14:14 UTCEPSS rescore
  22. 2026-06-08 14:14 UTCEPSS rescore
  23. 2026-06-07 15:22 UTCEPSS rescore
  24. 2026-06-07 15:22 UTCEPSS rescore
  25. 2026-06-06 13:45 UTCEPSS rescore
Show 27 more
  1. 2026-06-06 13:45 UTCEPSS rescore
  2. 2026-06-05 22:44 UTCEPSS rescore
  3. 2026-06-05 22:44 UTCEPSS rescore
  4. 2026-06-05 06:08 UTCEPSS rescore
  5. 2026-06-05 06:08 UTCEPSS rescore
  6. 2026-06-02 20:10 UTCEPSS rescore
  7. 2026-06-02 20:10 UTCEPSS rescore
  8. 2026-06-01 13:49 UTCEPSS rescore
  9. 2026-05-31 00:14 UTCEPSS rescore
  10. 2026-05-31 00:14 UTCEPSS rescore
  11. 2026-05-29 13:41 UTCEPSS rescore
  12. 2026-05-29 05:50 UTCEG score recompute
  13. 2026-05-29 05:50 UTCVendor advisory
  14. 2026-05-28 13:42 UTCEPSS rescore
  15. 2026-05-28 13:42 UTCEPSS rescore
  16. 2026-05-26 07:16 UTCEPSS rescore
  17. 2026-05-26 07:16 UTCEPSS rescore
  18. 2026-05-26 07:16 UTCEPSS rescore
  19. 2026-05-24 16:43 UTCEPSS rescore
  20. 2026-05-22 21:15 UTCEPSS rescore
  21. 2026-05-22 21:15 UTCEPSS rescore
  22. 2026-05-22 21:15 UTCEPSS rescore
  23. 2026-05-20 11:21 UTCEPSS rescore
  24. 2026-05-20 11:21 UTCEPSS rescore
  25. 2026-05-20 11:21 UTCEPSS rescore
  26. 2026-05-18 21:29 UTCEPSS rescore
  27. 2026-05-18 21:29 UTCEPSS rescore

Publicly available exploits

(2 references)

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

  • Metasploitauxiliary/dos/http/hashcollision_dos✓ verified
    First seen Dec 28, 2011

    Hashtable Collisions

    Open source ↗
  • Exploit-DBEDB-2012✓ verified
    First seen Jul 15, 2006

    MyBulletinBoard (MyBB) 1.1.5 - 'CLIENT-IP' SQL Injection

    Open source ↗

Frequently asked(4)

What is CVE-2011-4858?
CVE-2011-4858 is a none vulnerability published on January 5, 2012. Apache Tomcat before 5.5.35, 6.x before 6.0.35, and 7.x before 7.0.23 computes hash values for form parameters without restricting the ability to trigger hash collisions predictably, which allows remote attackers to cause a denial of service (CPU consumption) by sending many crafted parameters.
When was CVE-2011-4858 disclosed?
CVE-2011-4858 was first published in the National Vulnerability Database on January 5, 2012, with the most recent update on April 29, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2011-4858 actively exploited?
CVE-2011-4858 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 99.6% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
How do I remediate CVE-2011-4858?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2011-4858, 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-2011-4858

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