CVE-2020-11076— HTTP Smuggling via Transfer-Encoding Header in Puma
Quick assessment
Affected
puma puma
Exploitation
Public or AI PoC available; prioritize validation
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.
Puma是一款针对高并发应用的Web服务器。 Puma (RubyGem) 4.3.4之前版本和3.12.5之前版本中存在环境问题漏洞。攻击者可借助无效的transfer-encoding标头利用该漏洞实施HTTP走私攻击。
Possible ATT&CK Techniques 1 AI
T1190 · Exploit Public-Facing Application
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I. Basic Information for CVE-2020-11076
Vulnerability Information
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Vulnerability Title
HTTP Smuggling via Transfer-Encoding Header in Puma
Source: CVE Program / CVE List V5
Vulnerability Description
In Puma (RubyGem) before 4.3.4 and 3.12.5, an attacker could smuggle an HTTP response, by using an invalid transfer-encoding header. The problem has been fixed in Puma 3.12.5 and Puma 4.3.4.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Source: CVE Program / CVE List V5
Vulnerability Type
HTTP请求的解释不一致性(HTTP请求私运)
Source: CVE Program / CVE List V5
Vulnerability Title
Puma 环境问题漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Puma是一款针对高并发应用的Web服务器。 Puma (RubyGem) 4.3.4之前版本和3.12.5之前版本中存在环境问题漏洞。攻击者可借助无效的transfer-encoding标头利用该漏洞实施HTTP走私攻击。
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
II. Public POCs for CVE-2020-11076
| # | POC Description | Source Link | Shenlong Link |
|---|---|---|---|
| 1 | Puma, CVE-2020-11076 and CVE-2020-11077 | https://github.com/dentarg/cougar | POC Details |
AI-Generated POC
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Patches & Fixes for CVE-2020-11076 (1)
Vendor Advisories for CVE-2020-11076 (1)
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https://github.com/puma/puma/security/advisories/GHSA-x7jg-6pwg-fx5h x_refsource_CONFIRM
Mailing List Discussions for CVE-2020-11076 (4)
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http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00038.html vendor-advisory x_refsource_SUSE
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http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00034.html vendor-advisory x_refsource_SUSE
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https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SKIY5H67GJIGJL6SMFWFLUQQQR3EMVPR/ vendor-advisory x_refsource_FEDORA
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Other References for CVE-2020-11076 (1)
IV. Related Vulnerabilities
Same product: puma
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CVE-2023-40175
Inconsistent Interpretation of HTTP Requests in puma
Same weakness: CWE-444
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V. Comments for CVE-2020-11076
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