CVE-2023-27580

Password Shucking Vulnerability

Workarounds

None.

References

• https://cheatsheetseries.owasp.org/cheatsheets/Password_Storage_Cheat_Sheet.html#pre-hashing-passwords
• https://blog.ircmaxell.com/2015/03/security-issue-combining-bcrypt-with.html
• https://www.scottbrady91.com/authentication/beware-of-password-shucking

For more information

If you have any questions or comments about this advisory:

• Open an issue or discussion in codeigniter4/shield
• Email us at [email protected]

An improper implementation was found in the password storage process.

All hashed passwords stored in Shield v1.0.0-beta.3 or earlier are easier to crack than expected due to the vulnerability. Therefore, they should be removed as soon as possible.

If an attacker gets (1) the user's hashed password by Shield, and (2) the hashed password (SHA-384 hash without salt) from somewhere, the attacker may easily crack the user's password.

CVE-2023-27580 has a CVSS score of 5.9 (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 (1.0.0-beta.4); upgrading removes the vulnerable code path.

Kodem intelligence

Already deployed Kodem?

Upgrade to Shield v1.0.0-beta.4 or later.

After upgrading, all users’ hashed passwords should be updated (saved to the database).
See https://github.com/codeigniter4/shield/blob/develop/UPGRADING.md for details.

1. What is CVE-2023-27580? CVE-2023-27580 is a medium-severity security vulnerability in codeigniter4/shield (composer), affecting versions < 1.0.0-beta.4. It is fixed in 1.0.0-beta.4.
2. How severe is CVE-2023-27580? CVE-2023-27580 has a CVSS score of 5.9 (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 codeigniter4/shield are affected by CVE-2023-27580? codeigniter4/shield (composer) versions < 1.0.0-beta.4 is affected.
4. Is there a fix for CVE-2023-27580? Yes. CVE-2023-27580 is fixed in 1.0.0-beta.4. Upgrade to this version or later.
5. Is CVE-2023-27580 exploitable, and should I be worried? Whether CVE-2023-27580 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-2023-27580 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-2023-27580? Upgrade codeigniter4/shield to 1.0.0-beta.4 or later.

Other vulnerabilities in codeigniter4/shield