Summary
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.
Impact
CVE-2026-3515 has a CVSS score of 8.5 (High). The vector is network-reachable, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. No fixed version is listed yet, so configuration controls and monitoring matter more in the interim.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Remediation advice
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2026-3515? CVE-2026-3515 is a high-severity security vulnerability in prefect (pip), affecting versions <= 3.6.18. No fixed version is listed yet.
- How severe is CVE-2026-3515? CVE-2026-3515 has a CVSS score of 8.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of prefect are affected by CVE-2026-3515? prefect (pip) versions <= 3.6.18 is affected.
- Is there a fix for CVE-2026-3515? No fixed version is listed for CVE-2026-3515 yet. Monitor the advisory for updates and apply mitigations in the interim.
- Is CVE-2026-3515 exploitable, and should I be worried? Whether CVE-2026-3515 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-3515 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.