CVE-2021-21704

Status: ModifiedMedium (5.9)—

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

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Base score: 5.9

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 1.80%
Percentile among all scored CVEs: 78
Score date: 10/7/2026

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 (2)

Netapp — Clustered Data Ontap PHP — PHP

CWEs

CWE-125, CWE-190
CWE-787

References

Raw JSON (NVD)

Show

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    }
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  "lastModified": "2026-06-17T03:36:01.770",
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