PHP before 5.3.9 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.
CVE-2011-4885
This CVE was only ever scored under CVSS v2.0. NVD CVSS v2.0 base 5.0 — v2 rates that MEDIUM (v2 bands: LOW 0.0–3.9 / MEDIUM 4.0–6.9 / HIGH 7.0–10.0; v2 has no CRITICAL band). Vector AV:N/AC:L/Au:N/C:N/I:N/A:P. CVSS v2 is an older, coarser metric than v3.1/v4.0 (no Scope, no User Interaction, no Attack Requirements), so it is not directly comparable to a v3 or v4 score. NVD has never re-scored this record under v3. EPSS predicts 83.9% exploitation probability in the next 30 days, which is reflected in EG Risk but does not lift the v2 base. Confidence: LOW.
- High exploitation likelihood — EPSS 83%
- Public exploit code is available (Metasploit, Exploit-DB (verified), epss top5pct, epss high, public exploit)
A fix is available — apply it.
- CVSS v2.0 (legacy)
- 5.0MEDIUMNVD never assigned a CVSS v3 rating to this CVE
- EG Score
- 5.0(low)
- EG Risk
- 61(Track)EG Risk 61/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity50% × 45%Exploitation84% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 83%
- EPSS %ILE
- 100%
- KEV
- Not listed
Published
December 30, 2011
Last Modified
April 29, 2026
References (54)
- cve@mitrehttp://archives.neohapsis.com/archives/bugtraq/2011-12/0181.html
- cve@mitrehttp://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=c03360041
- cve@mitrehttp://lists.apple.com/archives/security-announce/2012/May/msg00001.html
- cve@mitrehttp://lists.opensuse.org/opensuse-security-announce/2012-03/msg00013.html
- cve@mitrehttp://lists.opensuse.org/opensuse-security-announce/2012-03/msg00016.html
- cve@mitrehttp://marc.info/?l=bugtraq&m=132871655717248&w=2
- cve@mitrehttp://marc.info/?l=bugtraq&m=133469208622507&w=2
- cve@mitrehttp://rhn.redhat.com/errata/RHSA-2012-0071.html
- cve@mitrehttp://secunia.com/advisories/47404
- cve@mitrehttp://secunia.com/advisories/48668
- cve@mitrehttp://support.apple.com/kb/HT5281
- cve@mitrehttp://svn.php.net/viewvc?view=revision&revision=321003
- cve@mitrehttp://svn.php.net/viewvc?view=revision&revision=321040
- cve@mitrehttp://www.debian.org/security/2012/dsa-2399
- cve@mitrehttp://www.exploit-db.com/exploits/18296
Patch Availability(4)
| Vendor / Ecosystem | Fixed in / Patch | Released | Source |
|---|---|---|---|
| ubuntu | libapache2-mod-php5 (5.3.6-13ubuntu3.5) @ oneiric | 2026-05-29 | ubuntu |
| redhat | php-0:4.3.9-3.35 | 2012-01-30 | redhat |
| redhat | php-0:5.1.6-27.el5_7.4 | 2012-01-18 | redhat |
| redhat | php-0:5.3.3-3.el6_2.5 | 2012-01-11 | redhat |
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
(2 across 2 ecosystems)
Debian:5.0(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| php5 | 5.2.6.dfsg.1-1+lenny10 ... 5.2.6.dfsg.1-1+lenny9 (10 versions) | 5.2.6.dfsg.1-1+lenny14 | — |
Debian:6.0(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| php5 | 5.3.3-7, 5.3.3-7+squeeze1, 5.3.3-7+squeeze2, 5.3.3-7+squeeze3 | 5.3.3-7+squeeze5 | — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
All Vendor Advisories
(4)
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 2× in last 7d / 7× 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.
- 2026-08-26 14:40 UTCEPSS rescore
- 2026-08-21 23:43 UTCEPSS rescore
- 2026-08-19 16:59 UTCEPSS rescore
- 2026-08-16 02:09 UTCEPSS rescore
- 2026-08-15 01:25 UTCEPSS rescore
- 2026-08-05 19:12 UTCEPSS rescore
- 2026-07-30 01:26 UTCEPSS rescore
- 2026-07-28 15:31 UTCEPSS rescore
- 2026-07-26 13:44 UTCEG score recompute▲ 5.00
- 2026-07-23 14:14 UTCEPSS rescore
- 2026-07-23 01:06 UTCEG score recompute▼ 8.80
- 2026-07-23 00:09 UTCEG score recompute▲ 8.80
- 2026-07-22 21:48 UTCEG score recompute▼ 9.00
- 2026-07-21 15:21 UTCEPSS rescore
- 2026-07-20 17:03 UTCEPSS rescore
- 2026-07-20 17:03 UTCEPSS rescore
- 2026-07-15 16:54 UTCEPSS rescore
- 2026-07-15 16:54 UTCEPSS rescore
- 2026-07-09 19:05 UTCEPSS rescore
- 2026-07-06 16:23 UTCEPSS rescore
- 2026-07-04 06:27 UTCEPSS rescore
- 2026-07-01 15:02 UTCEPSS rescore
- 2026-06-27 03:05 UTCEPSS rescore
- 2026-06-27 03:05 UTCEPSS rescore
- 2026-06-24 14:02 UTCEPSS rescore
Show 38 moreShow fewer
- 2026-06-24 14:02 UTCEPSS rescore
- 2026-06-23 21:30 UTCEPSS rescore
- 2026-06-21 14:53 UTCEPSS rescore
- 2026-06-21 01:56 UTCEPSS rescore
- 2026-06-21 01:56 UTCEPSS rescore
- 2026-06-16 17:49 UTCEPSS rescore
- 2026-06-16 17:49 UTCEPSS rescore
- 2026-06-15 17:44 UTCEPSS rescore
- 2026-06-13 22:57 UTCEPSS rescore
- 2026-06-12 23:08 UTCEPSS rescore
- 2026-06-11 13:56 UTCEPSS rescore
- 2026-06-10 22:14 UTCEPSS rescore
- 2026-06-05 22:44 UTCEPSS rescore
- 2026-06-05 22:44 UTCEPSS rescore
- 2026-06-04 13:09 UTCEPSS rescore
- 2026-06-02 20:10 UTCEPSS rescore
- 2026-06-02 20:10 UTCEPSS rescore
- 2026-06-01 13:49 UTCEPSS rescore
- 2026-05-31 22:28 UTCEPSS rescore
- 2026-05-31 22:28 UTCEPSS rescore
- 2026-05-31 00:14 UTCEPSS rescore
- 2026-05-31 00:14 UTCEPSS rescore
- 2026-05-29 13:41 UTCEPSS rescore
- 2026-05-29 05:52 UTCEG score recompute
- 2026-05-29 05:52 UTCVendor advisory
- 2026-05-29 05:52 UTCGHSA enrichment
- 2026-05-28 13:42 UTCEPSS rescore
- 2026-05-28 13:42 UTCEPSS rescore
- 2026-05-26 13:41 UTCEPSS rescore
- 2026-05-26 13:41 UTCEPSS rescore
- 2026-05-22 21:15 UTCEPSS rescore
- 2026-05-22 21:15 UTCEPSS rescore
- 2026-05-22 21:15 UTCEPSS rescore
- 2026-05-20 22:37 UTCEPSS rescore
- 2026-05-20 22:37 UTCEPSS rescore
- 2026-05-20 22:37 UTCEPSS rescore
- 2026-05-18 21:29 UTCEPSS rescore
- 2026-05-18 21:29 UTCEPSS rescore
Publicly available exploits
(4 references)Working exploit code is in the public domain (1 Metasploit module) (3 Exploit-DB entries). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.
- Exploit-DBEDB-18305✓ verifiedFirst seen Jan 3, 2012
PHP Hash Table Collision - Denial of Service (PoC)
Open source ↗ - Exploit-DBEDB-18296First seen Jan 1, 2012
PHP 5.3.8 - Hashtables Denial of Service
Open source ↗ - Metasploitauxiliary/dos/http/hashcollision_dos✓ verifiedFirst seen Dec 28, 2011
Hashtable Collisions
Open source ↗ - Exploit-DBEDB-2012✓ verifiedFirst seen Jul 15, 2006
MyBulletinBoard (MyBB) 1.1.5 - 'CLIENT-IP' SQL Injection
Open source ↗
Frequently asked(4)
What is CVE-2011-4885?
When was CVE-2011-4885 disclosed?
Is CVE-2011-4885 actively exploited?
How do I remediate CVE-2011-4885?
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2011-4885
Is Your Infrastructure Affected by CVE-2011-4885?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.