GHSA-R253-R9JW-QG44

The Docker API server accepted a request-supplied browser_config.extra_args, which flowed into Chromium's launch arguments. An attacker could inject Chromium switches that replace a child-process launch command (--utility-cmd-prefix, --renderer-cmd-prefix, --gpu-launcher, --browser-subprocess-path) together with --no-zygote, causing Chromium to fork/exec an attacker-controlled command as the container's runtime user. The Docker API is unauthenticated by default, so a single request yields arbitrary command execution.

The earlier extra_args SSRF patch (0.8.9) used a denylist scoped to proxy/DNS flags; a denylist of launch switches is inherently incomplete, and these command-execution switches were not covered.

Affected paths

/crawl, /crawl/stream, /crawl/job accepting a request browser_config.extra_args.

Workarounds

• Upgrade to the patched version (0.9.0).
• Enable authentication (CRAWL4AI_API_TOKEN) and restrict who can reach the API.
• Run the container with a restrictive seccomp profile and no ability to exec helper binaries.

Credits

Y4tacker - reported the --no-zygote + --utility-cmd-prefix command-injection chain with a confirmed in-container PoC and an allowlist/reject recommendation.
UDU_RisePho (hoanggxyuuki) - independently reported the request-supplied Chromium launch-flag RCE class (--renderer-cmd-prefix), confirmed still reproducing on 0.8.9.

Unauthenticated remote code execution as the container runtime user; full read/write of application data, mounted secrets, environment, and tokens, and out-of-band exfiltration independent of the HTTP response.

Untrusted input is evaluated as executable code within the application's runtime environment. Typical impact: arbitrary code execution within the application's privilege context.

GHSA-R253-R9JW-QG44 has a CVSS score of 10.0 (Critical). The vector is network-reachable, no 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. A fixed version is available (0.9.0); upgrading removes the vulnerable code path.

Kodem intelligence

0.9.0 establishes a trust boundary for request-supplied configuration: extra_args (along with other power fields such as proxy, user_data_dir, cdp_url, init_scripts) is a forbidden field for untrusted request bodies. Any request that sets extra_args is rejected with HTTP 400 rather than scrubbed against an always-incomplete denylist. In-process SDK callers (trusted) are unaffected.

1. What is GHSA-R253-R9JW-QG44? GHSA-R253-R9JW-QG44 is a critical-severity code injection vulnerability in crawl4ai (pip), affecting versions <= 0.8.9. It is fixed in 0.9.0. Untrusted input is evaluated as executable code within the application's runtime environment.
2. How severe is GHSA-R253-R9JW-QG44? GHSA-R253-R9JW-QG44 has a CVSS score of 10.0 (Critical). 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.
3. Which versions of crawl4ai are affected by GHSA-R253-R9JW-QG44? crawl4ai (pip) versions <= 0.8.9 is affected.
4. Is there a fix for GHSA-R253-R9JW-QG44? Yes. GHSA-R253-R9JW-QG44 is fixed in 0.9.0. Upgrade to this version or later.
5. Is GHSA-R253-R9JW-QG44 exploitable, and should I be worried? Whether GHSA-R253-R9JW-QG44 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
6. What actually determines whether GHSA-R253-R9JW-QG44 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.
7. How do I fix GHSA-R253-R9JW-QG44? Upgrade crawl4ai to 0.9.0 or later.