CVE-2026-45447 Details
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.
View at NVD
Exploit prediction scoring system (EPSS) score for CVE-2026-45447
EPSS (Exploit Prediction Scoring System): EPSS predicts the likelihood that a vulnerability will be exploited in the wild. A higher percentage means a greater chance of an exploit occurring. The EPSS model produces a probability score between 0 and 1 (0 and 100%).
2.72 Probability of exploitation activity being observed over the next 30 days (84th percentile)
CVSS score for CVE-2026-45447
CVSS (Common Vulnerability Scoring System): An open framework owned and managed by FIRST.Org, Inc. that assigns a numerical score from 0 to 10 to software vulnerabilities to indicate their severity.
8.8 High
Products affected by CVE-2026-45447
OpenSSL 1.1.1e
OpenSSL 1.1.1f
OpenSSL 1.1.1g
OpenSSL 1.1.1h
OpenSSL 1.1.1i
DVE Score by Bitsight AI
DVE scores complement traditional static scoring systems like CVSS with Bitsight AI powered real-time threat intelligence and underground cyber criminal activity so that security teams can reduce alert fatigue and focus on vulnerabilities most likely to be exploited.
Medium
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CVE-2026-45447 Global Footprint

Top 10 Identified Countries

Country Observations Percentage
US 25,468 28.00%
JP 10,288 11.31%
DE 5,831 6.41%
NL 3,462 3.81%
IN 3,172 3.49%
CA 3,105 3.41%
KR 3,024 3.32%
FR 2,935 3.23%
CN 2,914 3.20%
GB 2,506 2.75%

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CVE-2026-45447 Industry Footprint

Top 10 Identified Industries

*Service provider organizations (typically Technology and Telecommunications) are disproportionally represented in the results given their upstream ownership of end-user infrastructure. See our FAQs.

Industry* Observations Percentage
Technology 47,167 75.22%
Telecommunications 10,460 16.68%
Education 2,456 3.92%
Government/Politics 739 1.18%
Business Services 302 0.48%
Manufacturing 204 0.33%
Finance 159 0.25%
Healthcare/Wellness 154 0.25%
Media/Entertainment 131 0.21%
Food Production 128 0.20%

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