CVE-2026-5366
A public proof of concept exists; no exploitation attested.
- Published2026-06-20
- WeaknessCWE-94
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
Prefect version 3.6.23 is vulnerable to remote code execution due to improper handling of user-controlled input in the `GitRepository` storage class. The `commit_sha` parameter, which is passed to git commands, lacks validation and does not include a `--` separator to distinguish user input from git flags. This allows attackers to inject arbitrary git flags, such as `--upload-pack`, enabling execution of external programs. Additionally, the `directories` parameter can be exploited to inject git flags during sparse-checkout operations. These vulnerabilities allow any user with deployment creation permissions to execute arbitrary commands on worker machines, compromising shared work pools in multi-tenant environments.
Timeline
dates in UTC- 2026-06-2017:16CVE 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-2026-5366?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-5366?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 |
|---|---|---|---|
| 3.6 | = 3.6.23 | no fix published | NVD |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Fix
No fix published by the sources we read yet. NVD record
Detection
read 2026-10-23 19:25 UTC- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
Sources
- NVDCVE recordread 2026-10-23
- CISA-ADPSSVC decisionpoc2026-06-22
- OpenCVESSVC decisionpoc—
- CNACVSS 3.09.9read 2026-10-23
- CNAweakness (CWE)CWE-94read 2026-10-23
- FIRST EPSSEPSS score1.0 %2026-10-22
- PoC-in-GitHubproof of concept1read 2026-10-23
Technical details
- CVSS v3 Vector
- CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
- Published
- 2026-06-20
- Last Modified
- 2026-07-01
- NVD status
- Analyzed
Frequently asked questions
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