CVE-2021-21707

Exploitation

Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.

SSVC decision

Not assessed by CISA

EPSS probability

25.95% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 97.8% of scored records. A rank, not a probability.

NVD base score

5.3 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

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

NVD analysis status

Modified. NVD last modified this record on 2026-06-17.

Red Hat severity

Moderate. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2021-11-29 06:25Z4 YR AGO

Last updated

2024-09-17 03:38Z1 YR AGO

Reserved

2021-01-04

Assigning CNA

php

Record state

PUBLISHED

Severity

Medium (CVSS 5.3)

CNA CVSS vector

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

Weaknesses

• CWE-159Improper Handling of Invalid Use of Special ElementsClass
• CWE-20Improper Input ValidationClass

Data version

5.1

Document digest

a4a46dfed5f74682522e66ffb9ee1186afe5cee55d60c88d3b77919991db1245

• bugs.php.nethttps://bugs.php.net/bug.php?id=79971
• security.netapp.comhttps://security.netapp.com/advisory/ntap-20211223-0005/
• www.debian.orgDSA-5082https://www.debian.org/security/2022/dsa-5082vendor-advisory
• www.tenable.comhttps://www.tenable.com/security/tns-2022-09
• lists.debian.org[debian-lts-announce] 20221215 [SECURITY] [DLA 3243-1] php7.3 security updatehttps://lists.debian.org/debian-lts-announce/2022/12/msg00030.htmlmailing-list