SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-5366

Prefect version 3.6.23 is vulnerable to remote code execution due to improper handling of user-controlled input in the `GitRepository` storage class.

CRITICAL 9.9EPSS 1.03%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.03%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.0
9.9 CRITICALCVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
EPSS
1.03% probability · 62th percentile
CISA KEV
Not listed
Weakness
CWE-94
Affected
prefect/prefect
Source
security@huntr.dev

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.