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Vulnerability Assessment

Weakness
CWE
CWE-918
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V4 - API and Web Service URL allowlisting, SSRF prevention
MITRE ATT&CK

2 techniques across 2 tactics: Initial Access, Credential Access

The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up.

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Impact

CVSS score of 9.0 (CRITICAL). Attack characteristics: network attack vector, high complexity, no privileges required, no user interaction not required.
Exploit ScenarioDerived

A remote attacker could make the server perform requests to unintended internal or external resources by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability.
Act Now Prioritize within 24-48h. Why: In CISA KEV with patch available.
Exploited in the wild (CISA KEV) Patch available 100.0% exploitation probability (EPSS)

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AnalysisAI

A crafted request uri-path can cause mod_proxy to forward the request to an origin server choosen by the remote user.4.48 and earlier. Rated critical severity (CVSS 9.0), this vulnerability is remotely exploitable, no authentication required. This Server-Side Request Forgery (SSRF) vulnerability could allow attackers to make the server perform requests to unintended internal or external resources.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Validate and allowlist destination URLs, block requests to internal networks, use network segmentation.

Affects your stack

Find out whether the stacks and servers you run are on an affected version.

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

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Technical ContextAI · show details

This vulnerability is classified as Server-Side Request Forgery (SSRF) (CWE-918), which allows attackers to make the server perform requests to unintended internal or external resources. A crafted request uri-path can cause mod_proxy to forward the request to an origin server choosen by the remote user.4.48 and earlier. Affected products include: Resf Rocky Linux, Redhat Enterprise Linux, Redhat Enterprise Linux Eus, Redhat Enterprise Linux For Arm 64, Redhat Enterprise Linux For Arm 64 Eus.

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  • Exploit and PoC references, threat intelligence from 22 sources
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Severity by source

NVD PRIMARY 9.0 CRITICAL
AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High

Lifecycle Timeline

2
Added to CISA KEV
Jul 14, 2026 - 04:22 CISA
CVE Published
Sep 16, 2021 - 15:15 nvd
CRITICAL 9.0

DescriptionNVD

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.

Threat Intelligence Overview

Threat Score
7.8/10
Composite threat intelligence
EPSS Score
100.0%
Top 0% exploitable
Exploit
POC
Public exploit code exists
Data Quality
5 sources
Confidence: Medium
NVD CVE.org CISA KEV EPSS POC (1) VulDB

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity CRITICAL
CISA KEV Yes
Public POC Yes
EPSS 100.0%
Patch available Yes
Active threat Yes
Deciding rule
In CISA KEV with patch available
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived
Out-of-Cycle
Exploitation· derived
Active
System Exposure· derived
Open
Automatable· derived
No
Human Impact· derived
High

Priority Score

215
Low Medium High Critical
KEV: +50
EPSS: +100
CVSS: +45
PoC: +20
Weaponized: 0
Threat intel: 0
Gov advisory: 0

Attack Technique

Server-Side Request Forgery HIGH

Server-Side Request Forgery exploits applications that fetch remote resources based on user-supplied URLs.

Affected Products (CPE)NVD

cpe:2.3:o:resf:rocky_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_eus:8.1:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_eus:8.2:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_eus:8.4:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_eus:8.6:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_eus:8.8:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_for_arm_64:8.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_for_arm_64_eus:8.6:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_for_arm_64_eus:8.8:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems:7.0_s390x:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems:8.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems_eus:8.1:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems_eus:8.4:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems_eus:8.8:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems_eus_s390x:8.2:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_for_power_big_endian:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian:8.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian_eus:8.1:*:*:*:*:*:*:*
+ 63 more

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Same weakness CWE-918 – Server-Side Request Forgery (SSRF)

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CVE-2021-34473 CRITICAL POC
9.1
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CVE-2023-48022 CRITICAL POC
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Same technique SSRF

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References

Advisories & patches
PATCH https://www.oracle.com/security-alerts/cpuapr2022.html PATCH https://www.oracle.com/security-alerts/cpujan2022.html ADVISORY https://httpd.apache.org/security/vulnerabilities_24.html ADVISORY https://vuldb.com/vuln/182800 ADVISORY https://vuldb.com/vuln/190968 ADVISORY https://vuldb.com/vuln/197927 ADVISORY https://vuldb.com/vuln/198207 REF https://cert-portal.siemens.com/productcert/pdf/ssa-685781.pdf REF https://lists.apache.org/thread.html/r210807d0bb55f4aa6fbe1512be6bcc4dacd64e84940429fba329967a%40%3Cusers.httpd.apache.org%3E REF https://lists.apache.org/thread.html/r2eb200ac1340f69aa22af61ab34780c531d110437910cb9c0ece3b37%40%3Cbugs.httpd.apache.org%3E REF https://lists.apache.org/thread.html/r3925e167d5eb1c75def3750c155d753064e1d34a143028bb32910432%40%3Cusers.httpd.apache.org%3E REF https://lists.apache.org/thread.html/r61fdbfc26ab170f4e6492ef3bd5197c20b862ce156e9d5a54d4b899c%40%3Cusers.httpd.apache.org%3E REF https://lists.apache.org/thread.html/r82838efc5fa6fc4c73986399c9b71573589f78b31846aff5bd9b1697%40%3Cusers.httpd.apache.org%3E REF https://lists.apache.org/thread.html/r82c077663f9759c7df5a6656f925b3ee4f55fcd33c889ba7cd687029%40%3Cusers.httpd.apache.org%3E REF https://lists.apache.org/thread.html/rf6954e60b1c8e480678ce3d02f61b8a788997785652e9557a3265c00%40%3Cusers.httpd.apache.org%3E REF https://lists.debian.org/debian-lts-announce/2021/10/msg00001.html REF https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SPBR6WUYBJNACHKE65SPL7TJOHX7RHWD/ REF https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZNCYSR3BXT36FFF4XTCPL3HDQK4VP45R/ REF https://security.gentoo.org/glsa/202208-20 REF https://security.netapp.com/advisory/ntap-20211008-0004/ REF https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-httpd-2.4.49-VWL69sWQ REF https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-40438 REF https://www.debian.org/security/2021/dsa-4982 REF https://www.tenable.com/security/tns-2021-17

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