CVE-2020-27786
A public proof of concept exists; no exploitation attested.
- Published2020-12-11
- Fixed in5.6.14 · 5.4.42 · 4.19.124 · 4.14.181 · 4.9.224 · 4.4.224
- WeaknessCWE-416
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
A flaw was found in the Linux kernel’s implementation of MIDI, where an attacker with a local account and the permissions to issue ioctl commands to midi devices could trigger a use-after-free issue. A write to this specific memory while freed and before use causes the flow of execution to change and possibly allow for memory corruption or privilege escalation. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.
Timeline
dates in UTC- 2020-12-1105:15CVE publishedNVD
- 2026-10-2319:23First public proof of conceptPoC-in-GitHub
Observed activity
isMalicious corpus · updated 2026-10-23 18:48 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2020-27786?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2020-27786?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 |
|---|---|---|---|
| 5.x | ≥ 5.5, < 5.6.14 | 5.6.14 | NVD |
| 5.4 | ≥ 4.20, < 5.4.42 | 5.4.42 | NVD |
| 4.x | ≥ 4.15, < 4.19.124 | 4.19.124 | NVD |
| 4.x | ≥ 4.10, < 4.14.181 | 4.14.181 | NVD |
| 4.x | ≥ 4.5, < 4.9.224 | 4.9.224 | NVD |
| 4.4 | < 4.4.224 | 4.4.224 | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 4.4 | = 4.4 | no fix published | NVD |
| 4.5 | = 4.5 | no fix published | NVD |
| 4.6 | = 4.6 | no fix published | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 7.0 | = 7.0 | no fix published | NVD |
| 8.0 | = 8.0 | no fix published | NVD |
3 more products in the sources.
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Fix
- Update Linux linux kernel to 5.6.14 · 5.4.42 · 4.19.124 · 4.14.181 · 4.9.224 · 4.4.224
Advisories and patches
- bugzilla.redhat.comPatch
- git.kernel.orgPatch · Vendor Advisory
Detection
read 2026-10-23 19:23 UTC- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- 4 repositories, unverifiedkiks7/CVE-2020-27786-Kernel-Exploitelbiazo/CVE-2020-27786Trinadh465/linux-4.19.72_CVE-2020-27786ii4gsp/CVE-2020-27786 PoC-in-GitHub
Sources
- NVDCVSS 3.17.8read 2026-10-23
- NVDCVSS 2.07.2read 2026-10-23
- CNAweakness (CWE)CWE-416read 2026-10-23
- FIRST EPSSEPSS score1.7 %2026-10-22
- PoC-in-GitHubproof of concept4read 2026-10-23
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Published
- 2020-12-11
- Last Modified
- 2026-06-17
- NVD status
- Modified
Frequently asked questions
What is CVE-2020-27786?
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What is the CVSS score for CVE-2020-27786?
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