CVE-2026-24489

A vulnerability was discovered in Gakido that allowed HTTP Header Injection through CRLF (Carriage Return Line Feed) sequences in user-supplied header values and names.

When making HTTP requests with user-controlled header values containing \r\n (CRLF), \n (LF), or \x00 (null byte) characters, an attacker could inject arbitrary HTTP headers into the request.

Proof of Concept

from gakido import Client

# Before fix: X-Injected header would be sent as a separate header
c = Client(impersonate="chrome_120")
r = c.get("https://httpbin.org/headers", headers={
    "User-Agent": "test\r\nX-Injected: pwned"
})

# The server would receive:
# User-Agent: test
# X-Injected: pwned

Affected Code

The vulnerability existed in the header processing logic where user-supplied headers were not sanitized before being sent in HTTP requests.

File: gakido/headers.py
Function: canonicalize_headers()

An attacker who can control header values passed to Gakido's Client.get(), Client.post(), or other request methods could:

1. Inject arbitrary HTTP headers - Add malicious headers to requests
2. HTTP Response Splitting - Potentially manipulate responses in certain proxy configurations
3. Cache Poisoning - Inject headers that could poison intermediate caches
4. Session Fixation - Inject session-related headers
5. Bypass Security Controls - Inject headers that bypass server-side security checks

CVE-2026-24489 has a CVSS score of 5.3 (Medium). 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 (0.1.1); upgrading removes the vulnerable code path.

Kodem intelligence

The fix adds a _sanitize_header() function that strips \r, \n, and \x00 characters from both header names and values before they are included in HTTP requests.

def _sanitize_header(name: str, value: str) -> tuple[str, str]:
    """
    Sanitize header name and value to prevent HTTP header injection (CRLF injection).
    Strips CR, LF, and null bytes from both name and value.
    """
    clean_name = name.replace("\r", "").replace("\n", "").replace("\x00", "")
    clean_value = value.replace("\r", "").replace("\n", "").replace("\x00", "")
    return clean_name, clean_value

1. What is CVE-2026-24489? CVE-2026-24489 is a medium-severity security vulnerability in gakido (pip), affecting versions < 0.1.1. It is fixed in 0.1.1.
2. How severe is CVE-2026-24489? CVE-2026-24489 has a CVSS score of 5.3 (Medium). 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 gakido are affected by CVE-2026-24489? gakido (pip) versions < 0.1.1 is affected.
4. Is there a fix for CVE-2026-24489? Yes. CVE-2026-24489 is fixed in 0.1.1. Upgrade to this version or later.
5. Is CVE-2026-24489 exploitable, and should I be worried? Whether CVE-2026-24489 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 CVE-2026-24489 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 CVE-2026-24489? Upgrade gakido to 0.1.1 or later.