CVE-2020-11077
No exploitation reported by the sources we read.
- Published2020-05-22
- WeaknessCWE-444
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
Description
In Puma (RubyGem) before 4.3.5 and 3.12.6, a client could smuggle a request through a proxy, causing the proxy to send a response back to another unknown client. If the proxy uses persistent connections and the client adds another request in via HTTP pipelining, the proxy may mistake it as the first request's body. Puma, however, would see it as two requests, and when processing the second request, send back a response that the proxy does not expect. If the proxy has reused the persistent connection to Puma to send another request for a different client, the second response from the first client will be sent to the second client. This is a similar but different vulnerability from CVE-2020-11076. The problem has been fixed in Puma 3.12.6 and Puma 4.3.5.
Timeline
dates in UTC- 2020-05-2215:15CVE publishedNVD
Observed activity
isMalicious corpus · updated 2026-10-23 18:48 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2020-11077?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2020-11077?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 15.1 | = 15.1 | no fix published | NVD |
| 15.2 | = 15.2 | no fix published | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 4.x | ≥ 4.0.0, < 4.3.5 | 4.3.5 | NVD |
| 3.x | ≥ 3.0.0, < 3.12.6 | 3.12.6 | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 9.0 | = 9.0 | no fix published | NVD |
1 more product in the sources.
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Fix
Advisories and patches
- github.comRelease Notes
- github.comVendor Advisory
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
Sources
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- Published
- 2020-05-22
- Last Modified
- 2026-06-17
- NVD status
- Modified
Frequently asked questions
What is CVE-2020-11077?
Is CVE-2020-11077 actively exploited?
What is the CVSS score for CVE-2020-11077?
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Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.