Definition

MFA bypass attacks circumvent multi-factor authentication without cracking the second factor—typically by hijacking an already-authenticated session via stolen session tokens or cookies.

Key Points

  • citrixbleed-2 enables pre-auth memory leak of valid NetScaler session tokens; replay bypasses MFA challenges
  • Same primitive as CVE-2023-4966 CitrixBleed (Boeing, Comcast Xfinity breaches 2023)
  • Remediation requires session termination post-patch, not patching alone

Sources