CVE-2020-11076
HTTP Smuggling via Transfer-Encoding Header in Puma
HIGH
7.5
CVSS Score
Published: May 22, 2020 at 02:50 PM UTC
Updated: June 17, 2026 at 02:48 AM UTC
3 products affected across 3 vendorsDebian LinuxFedoraPuma
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Severity
HIGH7.5
Exploit prediction
EPSS 4%
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.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
Debian Linux· Debiandrupal
95%95%
v < 3.12.5v < 4.3.43.0.0 ≤ v < 3.12.64.0.0 ≤ v < 4.3.5
Affected range stops below 3.12.5, so it looks safe — our inference, not a vendor statement
Affected range stops below 3.12.6, so it looks safe — our inference, not a vendor statement
Affected range stops below 4.3.4, so it looks safe — our inference, not a vendor statement
Affected range stops below 4.3.5, so it looks safe — our inference, not a vendor statement
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
Patch and advisory references
- http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00034.html
- http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00038.html
- https://github.com/puma/puma/commit/f24d5521295a2152c286abb0a45a1e1e2bd275bd
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SKIY5H67GJIGJL6SMFWFLUQQQR3EMVPR/
References (7)
Vendor Advisoryx_refsource_SUSEMailing ListThird Party Advisory
Source: [email protected]
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00034.htmlVendor Advisoryx_refsource_SUSEMailing ListThird Party Advisory
Source: [email protected]
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00038.htmlx_refsource_MISCRelease Notes
Source: [email protected]
https://github.com/puma/puma/blob/master/History.md#434435-and-31253126--2020-05-22x_refsource_MISCPatch
Source: [email protected]
https://github.com/puma/puma/commit/f24d5521295a2152c286abb0a45a1e1e2bd275bdx_refsource_CONFIRMThird Party Advisory
Source: [email protected]
https://github.com/puma/puma/security/advisories/GHSA-x7jg-6pwg-fx5hMailing Listx_refsource_MLISTThird Party Advisory
Source: [email protected]
https://lists.debian.org/debian-lts-announce/2020/10/msg00009.htmlVendor Advisoryx_refsource_FEDORA
Source: [email protected]
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SKIY5H67GJIGJL6SMFWFLUQQQR3EMVPR/CVSS
7.5HIGHGitHub_M
- Attack Vector
- NETWORK
- Complexity
- LOW
- Privileges
- NONE
- User Interaction
- NONE
- Scope
- UNCHANGED
- Confidentiality
- NONE
- Integrity
- HIGH
- Availability
- NONE
Vector?
Quick Info
StatusMODIFIED
CWE
CWE-444
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