CVE-2009-4418
Status: ModifiedMedium (5)—
Severity5Medium · CVSS 2.0
Exploitation probability0.97 %higher than 62% of CVEs
Active exploitationNonot in the CISA catalog
Public exploitNot knownno public code found
The unserialize function in PHP 5.3.0 and earlier allows context-dependent attackers to cause a denial of service (resource consumption) via a deeply nested serialized variable, as demonstrated by a string beginning with a:1: followed by many {a:1: sequences.
CVSS
- Base score
- 5
- Version
- 2.0
- Vector
- AV:N/AC:L/Au:N/C:N/I:N/A:P
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days
- 0.97 %
- Percentile among all scored CVEs
- 62
- Score date
- 10/23/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (1)
CWEs
- CWE-189
References
Show 4 references
Raw JSON (NVD)
Show
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"id": "CVE-2009-4418",
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"vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:P",
"authentication": "NONE",
"integrityImpact": "NONE",
"accessComplexity": "LOW",
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"published": "2009-12-24T17:30:00.233",
"references": [
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"url": "http://www.suspekt.org/2009/11/28/shocking-news-in-php-exploitation/",
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"comment": "Red Hat does not consider this to be a security flaw. For further details, see https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2009-4418",
"lastModified": "2010-01-04T00:00:00",
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