[8.x] [JWT Integration] Fix for error handling in ParseWithClaims can lead to potentially dangerous situations

[ngadeg]

Proposed commit message

Unclear documentation of the error behavior in ParseWithClaims can lead to situation where users are potentially not checking errors in the way they should be. Especially, if a token is both expired and invalid, the errors returned by ParseWithClaims return both error codes. If users only check for the jwt.ErrTokenExpired using error.Is, they will ignore the embedded jwt.ErrTokenSignatureInvalid and thus potentially accept invalid tokens.

token, err := /* jwt.Parse or similar */
if token.Valid {
	fmt.Println("You look nice today")
} else if errors.Is(err, jwt.ErrTokenMalformed) {
	fmt.Println("That's not even a token")
} else if errors.Is(err, jwt.ErrTokenUnverifiable) {
	fmt.Println("We could not verify this token")
} else if errors.Is(err, jwt.ErrTokenSignatureInvalid) {
	fmt.Println("This token has an invalid signature")
} else if errors.Is(err, jwt.ErrTokenExpired) || errors.Is(err, jwt.ErrTokenNotValidYet) {
	// Token is either expired or not active yet
	fmt.Println("Timing is everything")
} else {
	fmt.Println("Couldn't handle this token:", err)
}

WeaknessCWE-347
WeaknessCWE-755
\

Checklist

• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have made corresponding change to the default configuration files
• I have added tests that prove my fix is effective or that my feature works
• I have added an entry in CHANGELOG.next.asciidoc or CHANGELOG-developer.next.asciidoc.

[cla-checker-service]

💚 CLA has been signed

[botelastic]

This pull request doesn't have a Team:<team> label.

[mergify]

This pull request does not have a backport label.
If this is a bug or security fix, could you label this PR @ngadeg? 🙏.
For such, you'll need to label your PR with:

• The upcoming major version of the Elastic Stack
• The upcoming minor version of the Elastic Stack (if you're not pushing a breaking change)

To fixup this pull request, you need to add the backport labels for the needed
branches, such as:

• backport-8./d is the label to automatically backport to the 8./d branch. /d is the digit

[mergify]

backport-8.x has been added to help with the transition to the new branch 8.x.
If you don't need it please use backport-skip label and remove the backport-8.x label.

[kaltaranodua]

Fixes vulnerability identified as CVE-2024-51744. This update addresses the issue with great improvements and ensures better security.

[ngadeg]

/cla