CVE-2020-11076

HTTP Smuggling via Transfer-Encoding Header in Puma

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.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.37% Top 25%
Vendor Advisory opensuse.org Vendor Advisory opensuse.org Vendor Advisory fedoraproject.org
Affected: puma puma
Published at:
Updated at:

References

Link Tags
https://github.com/puma/puma/security/advisories/GHSA-x7jg-6pwg-fx5h third party advisory
https://github.com/puma/puma/blob/master/History.md#434435-and-31253126--2020-05-22 release notes
https://github.com/puma/puma/commit/f24d5521295a2152c286abb0a45a1e1e2bd275bd patch
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00034.html mailing list third party advisory vendor advisory
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00038.html mailing list third party advisory vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SKIY5H67GJIGJL6SMFWFLUQQQR3EMVPR/ vendor advisory
https://lists.debian.org/debian-lts-announce/2020/10/msg00009.html third party advisory mailing list

Frequently Asked Questions

What is the severity of CVE-2020-11076?
CVE-2020-11076 has been scored as a high severity vulnerability.
How to fix CVE-2020-11076?
To fix CVE-2020-11076, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-11076 being actively exploited in the wild?
It is possible that CVE-2020-11076 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-11076?
CVE-2020-11076 affects puma puma.
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