CVE-2026-33753: Insecure Certificate Leaf Identification

Identifying a leaf certificate in an unordered PKCS#7 bag by simply finding a certificate whose subject does not match any other certificate's issuer is insecure. An attacker can trick this heuristic by injecting a spoofed certificate that matches the target requirements and does not act as an issuer. Instead, identify the leaf certificate using cryptographi

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greprules fetch cve-2026-33753-insecure-certificate-leaf-identification --engine opengrep

Description

Identifying a leaf certificate in an unordered PKCS#7 bag by simply finding a certificate whose subject does not match any other certificate's issuer is insecure. An attacker can trick this heuristic by injecting a spoofed certificate that matches the target requirements and does not act as an issuer. Instead, identify the leaf certificate using cryptographi