CVE-2021-21704 - CVE House
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Status published Medium CVE-2021-21704

Multiple vulnerabilities in Firebird client extension

Vulnerability Description

In PHP versions 7.3.x below 7.3.29, 7.4.x below 7.4.21 and 8.0.x below 8.0.8, when using Firebird PDO driver extension, a malicious database server could cause crashes in various database functions, such as getAttribute(), execute(), fetch() and others by returning invalid response data that is not parsed correctly by the driver. This can result in crashes, denial of service or potentially memory corruption.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • reported by trichimtrich at gmail dot com

References

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Affected Vendor

Affected Software

PHP
Vulnerable Versions:
7.3.x, 7.4.x, 8.0.X

Timeline

Official Publish: October 4th, 2021
Last Modified: September 17th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:L

Weaknesses (CWE)

CWE-125 CWE-190

MITRE ATT&CK TTPs

T1190 Exploit Public-Facing Application
Initial Access
T1213 Data from Information Repositories
Collection
T1003 OS Credential Dumping
Credential Access
T1552 Unsecured Credentials
Credential Access
T1068 Exploitation for Privilege Escalation
Privilege Escalation
T1055 Process Injection
Defense Evasion
T1105 Ingress Tool Transfer
Command and Control
T1499 Endpoint Denial of Service
Impact