PHP up to 7.1.5 Zend/zend_string.h zend_string_extend Negative Length out-of-bounds write

CVSS Meta Temp Score
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CTI Interest Score
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7.4$0-$5k0.00

Summaryinfo

A vulnerability labeled as problematic has been found in PHP up to 7.1.5. Impacted is the function zend_string_extend of the file Zend/zend_string.h. Such manipulation as part of Negative Length leads to input validation. This vulnerability is documented as CVE-2017-8923. The attack can be executed remotely. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in PHP up to 7.1.5 (Programming Language Software). Affected by this issue is the function zend_string_extend of the file Zend/zend_string.h. The manipulation as part of a Negative Length leads to a input validation vulnerability. Using CWE to declare the problem leads to CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. Impacted is availability. CVE summarizes:

The zend_string_extend function in Zend/zend_string.h in PHP through 7.1.5 does not prevent changes to string objects that result in a negative length, which allows remote attackers to cause a denial of service (application crash) or possibly have unspecified other impact by leveraging a script's use of .= with a long string.

The bug was discovered 05/12/2017. The weakness was released 05/12/2017 (Website). The advisory is shared for download at securityfocus.com. This vulnerability is handled as CVE-2017-8923 since 05/12/2017. The attack may be launched remotely. No form of authentication is required for exploitation. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 100420 (PHP 7.0.x < 7.0.19 Multiple Vulnerabilities), which helps to determine the existence of the flaw in a target environment. It is assigned to the family CGI abuses and running in the context r.

Upgrading eliminates this vulnerability. A possible mitigation has been published even before and not after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (100420) and SecurityFocus (BID 98518†). Entry connected to this vulnerability is available at VDB-101538. If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.6
VulDB Meta Temp Score: 7.4

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
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NVD Base Score: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 100420
Nessus Name: PHP 7.0.x < 7.0.19 Multiple Vulnerabilities
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

05/11/2017 🔍
05/12/2017 +1 days 🔍
05/12/2017 +0 days 🔍
05/12/2017 +0 days 🔍
05/12/2017 +0 days 🔍
05/12/2017 +0 days 🔍
05/13/2017 +1 days 🔍
05/25/2017 +12 days 🔍
12/27/2024 +2773 days 🔍

Sourcesinfo

Product: php.org

Advisory: 74577⛔
Researcher: whitehat002
Status: Confirmed

CVE: CVE-2017-8923 (🔍)
GCVE (CVE): GCVE-0-2017-8923
GCVE (VulDB): GCVE-100-101216
SecurityFocus: 98518
OSVDB: - CVE-2017-8923 - PHP - Denial of Service Issue

See also: 🔍

Entryinfo

Created: 05/13/2017 09:15
Updated: 12/27/2024 17:57
Changes: 05/13/2017 09:15 (66), 09/26/2020 11:36 (6), 12/23/2020 13:50 (3), 12/06/2022 12:26 (3), 12/27/2024 17:57 (19)
Complete: 🔍
Cache ID: 216:57C:103

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