CVE-2021-44224— Possible NULL dereference or SSRF in forward proxy configurations in Apache HTTP Server 2.4.51 and earlier
Quick assessment
Affected
Apache Software Foundation Apache HTTP Server
Exploitation
High exploitation probability; assess promptly
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.
Apache HTTP Server是美国阿帕奇（Apache）基金会的一款开源网页服务器。该服务器具有快速、可靠且可通过简单的API进行扩充的特点。 Apache HTTP Server 中存在代码问题漏洞，该漏洞源于产品存在空指针引用错误。攻击者可通过该漏洞导致系统奔溃或服务端请求伪造。以下产品及版本受到影响： Apache HTTP Server 2.4.7 至 2.4.51 版本。
Possible ATT&CK Techniques 2 AI
T1557 · Adversary-in-the-Middle T1190 · Exploit Public-Facing Application
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I. Basic Information for CVE-2021-44224
Vulnerability Information
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Vulnerability Title
Possible NULL dereference or SSRF in forward proxy configurations in Apache HTTP Server 2.4.51 and earlier
Source: CVE Program / CVE List V5
Vulnerability Description
A crafted URI sent to httpd configured as a forward proxy (ProxyRequests on) can cause a crash (NULL pointer dereference) or, for configurations mixing forward and reverse proxy declarations, can allow for requests to be directed to a declared Unix Domain Socket endpoint (Server Side Request Forgery). This issue affects Apache HTTP Server 2.4.7 up to 2.4.51 (included).
Source: CVE Program / CVE List V5
CVSS Information
N/A
Source: CVE Program / CVE List V5
Vulnerability Type
空指针解引用
Source: CVE Program / CVE List V5
Vulnerability Title
Apache HTTP Server 代码问题漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Apache HTTP Server是美国阿帕奇（Apache）基金会的一款开源网页服务器。该服务器具有快速、可靠且可通过简单的API进行扩充的特点。 Apache HTTP Server 中存在代码问题漏洞，该漏洞源于产品存在空指针引用错误。攻击者可通过该漏洞导致系统奔溃或服务端请求伪造。以下产品及版本受到影响： Apache HTTP Server 2.4.7 至 2.4.51 版本。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
| Vendor | Product | Affected Versions | CPE | Subscribe |
|---|---|---|---|---|
| Apache Software Foundation | Apache HTTP Server | 2.4.7 ~ Apache HTTP Server 2.4* | - |
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II. Public POCs for CVE-2021-44224
| # | POC Description | Source Link | Shenlong Link |
|---|
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Vendor Advisories for CVE-2021-44224 (9)
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https://support.apple.com/kb/HT213257 x_refsource_CONFIRM
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https://www.oracle.com/security-alerts/cpuapr2022.html x_refsource_MISC
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https://support.apple.com/kb/HT213255 x_refsource_CONFIRM
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http://httpd.apache.org/security/vulnerabilities_24.html x_refsource_MISC
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https://support.apple.com/kb/HT213256 x_refsource_CONFIRM
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https://security.netapp.com/advisory/ntap-20211224-0001/ x_refsource_CONFIRM
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https://www.oracle.com/security-alerts/cpujan2022.html x_refsource_MISC
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🔗 Apache HTTPD: Multiple Vulnerabilities (GLSA 202208-20) — Gentoo security Read full article vendor-advisory x_refsource_GENTOO
Mailing List Discussions for CVE-2021-44224 (8)
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https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X73C35MMMZGBVPQQCH7LQZUMYZNQA5FO/ vendor-advisory x_refsource_FEDORA
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https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RGWILBORT67SHMSLYSQZG2NMXGCMPUZO/ vendor-advisory x_refsource_FEDORA
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https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Z7H26WJ6TPKNWV3QKY4BHKUKQVUTZJTD/ vendor-advisory x_refsource_FEDORA
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https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BFSWOH4X77CV7AH7C4RMHUBDWKQDL4YH/ vendor-advisory x_refsource_FEDORA
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Other References for CVE-2021-44224 (2)
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https://www.tenable.com/security/tns-2022-03 x_refsource_CONFIRM
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https://www.tenable.com/security/tns-2022-01 x_refsource_CONFIRM
Same Patch Batch · Apache Software Foundation · 2021-12-20 · 3 CVEs total
| CVE-2021-44790 | Possible buffer overflow when parsing multipart content in mod_lua of Apache HTTP Server 2 | |
| CVE-2021-41561 | Apache Parquet-MR potential DoS in case of malicious Parquet file |
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V. Comments for CVE-2021-44224
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