Home › Exploited CVEs › CVE-2021-40438
CVE-2021-40438: Apache HTTP Server-Side Request Forgery (SSRF)
Apache Apache · in CISA KEV since 2021-12-01
2021-12-01added to KEV
2021-12-15federal remediation due date
100.00%EPSS exploit probability (30 days) 100.0th percentile
9 CRITICALCVSS 3.1
Knownknown ransomware use
76days from NVD publication to KEV
What it is
A crafted request uri-path can cause mod_proxy to forward the request to an origin server choosen by the remote user. This issue affects Apache HTTP Server 2.4.48 and earlier.
Required action (CISA)
Apply updates per vendor instructions.
| CWE | CWE-918 |
|---|---|
| CVSS vector | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H |
| NVD published | 2021-09-16 (Analyzed) |
Original records: NVD · CISA KEV · JSON: /api/cve/CVE-2021-40438.json · all KEV CVEs
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Get the full file: Exploited Vulnerabilities Brief – September 2026 ($29): this month's KEV additions ranked by EPSS, ransomware use and due date, ready to hand to a patch team. Checkout by Polar.