Memory corruption via UTF-32LE stack buffer overwrite
Published Apr 1, 2020 · Updated Sep 17, 2024
Stack-based buffer overflow in PHP 7.3 before 7.3.16 and 7.4 before 7.4.4 allows attackers to corrupt memory via invalid UTF-32LE input. In mb_strtolower(), php_unicode_tolower_full copies an oversized case-conversion result from read-only data into a stack buffer without validating the destination bound. Reachability requires mbstring code to pass crafted UTF-32LE text to mb_strtolower(); the demonstrated outcome is a process crash, while the CNA also records potential code execution.
Summary
What happened
Stack-based buffer overflow in PHP 7.3 before 7.3.16 and 7.4 before 7.4.4 allows attackers to corrupt memory via invalid UTF-32LE input. In mb_strtolower(), php_unicode_tolower_full copies an oversized case-conversion result from read-only data into a stack buffer without validating the destination bound. Reachability requires mbstring code to pass crafted UTF-32LE text to mb_strtolower(); the demonstrated outcome is a process crash, while the CNA also records potential code execution.
The record
- CVE
- CVE-2020-7065
- Published
- Apr 1, 2020
- Updated
- Sep 17, 2024
- Vendor
- The PHP Group
- Product
- PHP
- Classifications
- CWE-121, CWE-787
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 1, 2020CVE publishedPublication date reported by the CVE source.
- Sep 17, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=7.3.x <7.3.16
- Affected versionversion=7.4.x <7.4.4
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
- PHP bug 79371 reproducerproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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