CVE-2021-42125
Published: 07 December 2021
Summary
CVE-2021-42125 is a high-severity Deserialization of Untrusted Data (CWE-502) vulnerability in Ivanti Avalanche. Its CVSS base score is 8.8 (High).
Operationally, ranked in the top 1.5% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2021-29110
Vulnerability details
An unrestricted file upload vulnerability exists in Ivanti Avalanche before 6.3.3 allows an attacker with access to the Inforail Service to write dangerous files.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Untrusted serialized data can be deserialized and observed inside the chamber, blocking gadget-chain exploitation outside the sandbox.
Scans files from external sources on download/open/execute, blocking unrestricted uploads of dangerous file types.
Penetration testing supplies malicious serialized objects, detecting unsafe deserialization and supporting corrective actions.
Requiring identifiable owners for portable devices reduces the attack surface for unrestricted uploads of dangerous file types via anonymous media.
Evaluation of untrusted data handling (deserialization testing) reveals unsafe processing, which the required remediation process addresses.
Prevents unrestricted writing of arbitrary or malicious firmware by keeping hardware write-protect enabled except under tightly controlled manual procedures.
Validates or rejects untrusted serialized data before deserialization occurs.
Integrity verification of serialized information can detect tampering before deserialization occurs.