What is CVE-2009-4186?

CVE-2009-4186 is a vulnerability in Apple Safari, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. Published 2009-12-03.

Is CVE-2009-4186 known to be exploited?

4 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Buffer overflow in Apple Safari

CVE-2009-4186

Stack consumption vulnerability in Apple Safari 4.0.3 on Windows allows remote attackers to cause a denial of service (application crash) via a long URI value (aka url) in the Cascading Style Sheets (CSS) background property.

Vulnerability class: Buffer Overflow

Published 2009-12-03 · last modified 2026-06-16.

CVSS v2 metric

CVSS v2 base score 9.3 (High). Vector: AV:N/AC:M/Au:N/C:C/I:C/A:C. This CVE predates CVSS v3 and has no v3 score from NVD.

EPSS exploit prediction

EPSS: 0.065 (93.6th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 94th percentile — 93.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.065 · newest: 0.065 · change: 0.000

Affected products

Apple Safari — versions 4.0.3
Microsoft Windows

Weakness classification (CWE)

CWE-119 — Improper Restriction of Operations within the Bounds of a Memory Buffer

Public proof-of-concept exploits

References

exchange.xforce.ibmcloud.com/vulnerabilities/54487 (vdb-entry)
www.exploit-db.com/exploits/10102 (Exploit, exploit)
www.securityfocus.com/bid/37039 (Exploit, vdb-entry)

Frequently asked questions

What is CVE-2009-4186?: CVE-2009-4186 is a vulnerability in Apple Safari, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. Published 2009-12-03.
Is CVE-2009-4186 known to be exploited?: 4 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.