CVE-2026-45447

Published Jun 9, 2026

Last updated 4 days ago

CVSS high 8.8
Ubuntu

Overview

Description
Issue summary: A specially crafted PKCS#7 or S/MIME signed message could trigger a use-after-free during PKCS#7 signature verification. Impact summary: A use-after-free may result in process crashes, heap corruption, or potentially remote code execution. When processing a PKCS#7 or S/MIME signed message, if the SignedData digestAlgorithms field is present as an empty ASN.1 SET, OpenSSL may incorrectly free a caller-owned BIO during PKCS7_verify(). A subsequent use of the BIO by the calling application results in a use-after-free condition. In the common case this occurs when the application later calls BIO_free() on the BIO originally passed to PKCS7_verify(). Depending on allocator behavior and application-specific BIO usage patterns, this may result in a crash or other memory corruption. In some application contexts this may potentially be exploitable for remote code execution. Applications that process PKCS#7 or S/MIME signed messages using OpenSSL PKCS#7 APIs may be affected. Applications using the CMS APIs for this processing are not affected. The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.
Source
openssl-security@openssl.org
NVD status
Awaiting Analysis

Risk scores

CVSS 3.1

Type
Secondary
Base score
8.8
Impact score
5.9
Exploitability score
2.8
Vector string
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

Weaknesses

openssl-security@openssl.org
CWE-416

Social media

Hype score
Not currently trending

  1. 何十年も専門家のレビューをくぐり抜けてきた脆弱性を、AIが掘り起こし始めました。 2026年6月9日、OpenSSLプロジェクトが高危険度の脆弱性「CVE-2026-45447」を含む計18件の脆弱性を公表し、修正版を公開しまし

    @TrinityDox_JP

    12 Jun 2026

    202 Impressions

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    1 Like

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  2. OpenSSL patches 16 flaws: CVE-2026-45447, heap use-after-free in PKCS7_verify() with RCE potential via crafted S/MIME. Also: unauthenticated QUIC DoS (CVE-2026-34183) and key forgery (CVE-2026-34182). Check static builds. https://t.co/k5NcivCF2t #CyberSecu https://t.co/nC2CFxcNTX

    @securitydailyr

    11 Jun 2026

    41 Impressions

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Related CVEs

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References

Sources include official advisories and independent security research.