CVE-2026-3515 | Argument Injection in prefecthq/prefect

A vulnerability in the `GitHubRepository` block of the `prefect-github` integration in Prefect version 3.6.18 allows an attacker to inject arbitrary git command-line options via the `reference` field. The `reference` field is concatenated directly into a `git clone` command string without proper sanitization, and then parsed by `shlex.split()`. This enables injection of options such as `-c`, leading to potential Server-Side Request Forgery (SSRF), credential theft, or remote code execution (RCE). The vulnerability affects both the `aget_directory()` and `get_directory()` methods in `src/integrations/prefect-github/prefect_github/repository.py`. This issue does not affect the GitLab and BitBucket integrations, which use a safer list-based command construction approach.

Published: 2026-05-24 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Awaiting Analysis，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-3515 is rated Moderate Risk (44.8/100): CVSS High severity, with low exploitation likelihood (EPSS 0.38%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-3515

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.10% 0.38% +0.29%
2 2026-05-24 — 0.10% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-3515

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.5 3.0 HIGH
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 3.1 4.7 [email protected]

Weakness enumeration for CVE-2026-3515

GitHub Security Advisory for CVE-2026-3515

GHSA-cw25-2p92-7f75 · Severity: high — A vulnerability in the `GitHubRepository` block of the `prefect-github` integration in Prefect...

Affected software / configurations for CVE-2026-3515

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-3515

cvelogic Threat Intelligence