CVE-2021-43557

The uri-block plugin in Apache APISIX before 2.10.2 uses $request_uri without verification. The $request_uri is the full original request URI without normalization. This makes it possible to construct a URI to bypass the block list on some occasions. For instance, when the block list contains "^/internal/", a URI like `//internal/` can be used to bypass it. Some other plugins also have the same issue. And it may affect the developer's custom plugin.

CVSS v3.0 7.5 HIGH
CVSS v2.0 5.0 MEDIUM

7.5^/10

CVSS v3.0 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

5.0^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:L/Au:N/C:P/I:N/A:N

Exploitability : 10.0 / Impact : 2.9

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact NONE

Availability Impact NONE

References

Link	Resource
https://lists.apache.org/thread/18jyd458ptocr31rnkjs71w4h366mv7h	Exploit Mailing List Vendor Advisory
http://www.openwall.com/lists/oss-security/2021/11/22/2	Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/11/22/1	Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/11/23/1	Exploit Mailing List Third Party Advisory

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Configurations

Configuration 1 (hide)

cpe:2.3:a:apache:apisix:*:*:*:*:*:*:*:*

Information

Published : 2021-11-22 01:15

Updated : 2021-11-26 07:47

NVD link : CVE-2021-43557

Mitre link : CVE-2021-43557

JSON object : View

CWE

CWE-77

Improper Neutralization of Special Elements used in a Command ('Command Injection')

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Products Affected

apache

apisix

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