Weakness · High
CWE-347: Improper Verification of Cryptographic Signature
What it is
The product does not verify, or incorrectly verifies, the cryptographic signature for data.
- Severity (our rating)
- High
- Likelihood of exploit
- Not rated by MITRE
- Introduced during
- Architecture and Design, Implementation
- Exploited in the wild
- 6 known exploited CVEs
What an attacker can do
- Gain Privileges or Assume Identity (Access Control, Integrity, Confidentiality)
- Modify Application Data (Access Control, Integrity, Confidentiality)
- Execute Unauthorized Code or Commands (Access Control, Integrity, Confidentiality)
How to prevent it
MITRE lists no specific mitigation for this weakness. Treat it like its parent weaknesses below: validate input, keep the design simple and review the code where it could appear.
How to find it
- Automated Static Analysis. Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)
Exploited in the wild: 6 CVEs
Vulnerabilities caused by CWE-347 that attackers have used, from CISA's Known Exploited Vulnerabilities catalog, newest first.
- CVE-2026-5430WSO2 Multiple Products Path Traversal Vulnerability · added September 24, 2026
- CVE-2026-48558SimpleHelp Authentication Bypass Vulnerability · added June 29, 2026
- CVE-2025-59718Fortinet Multiple Products Improper Verification of Cryptographic Signature Vulnerability · added December 16, 2025
- CVE-2020-2021 ransomwarePalo Alto Networks PAN-OS Authentication Bypass Vulnerability · added March 25, 2022
- CVE-2022-20703Cisco Small Business RV Series Routers Stack-based Buffer Overflow Vulnerability · added March 3, 2022
- CVE-2020-1464Microsoft Windows Spoofing Vulnerability · added November 3, 2021
H2 Security
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Start freeSource: MITRE Common Weakness Enumeration, CWE version 4.19.1. CWE is a trademark of The MITRE Corporation.