SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2021-21704

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…

MEDIUM 5.9EPSS 1.80%

Does this matter?

Lower severity and a low EPSS score (1.80%). Track it; it rarely justifies an emergency change on its own.

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.

CVSS 3.1
5.9 MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
1.80% probability · 78th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-125, CWE-190, CWE-787
Affected
php/php · netapp/clustered data ontap
Source
security@php.net
EPSS trend
0%3%5%26 October 2026: 1.80%26 October 202626 October 2026

EPSS 1.8% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.