CVE-2026-45447 (GCVE-0-2026-45447)

Vulnerability from cvelistv5 – Published: 2026-06-09 16:03 – Updated: 2026-06-10 03:59
VLAI
Title
Heap Use-After-Free in the PKCS7_verify() Function
Summary
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.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
Assigner
References
Impacted products
Vendor Product Version
OpenSSL OpenSSL Affected: 4.0.0 , < 4.0.1 (semver)
Affected: 3.6.0 , < 3.6.3 (semver)
Affected: 3.5.0 , < 3.5.7 (semver)
Affected: 3.4.0 , < 3.4.6 (semver)
Affected: 3.0.0 , < 3.0.21 (semver)
Affected: 1.1.1 , < 1.1.1zh (custom)
Affected: 1.0.2 , < 1.0.2zq (custom)
Create a notification for this product.
Date Public
2026-06-09 14:00
Credits
Thai Duong (Calif.io in collaboration with Claude and Anthropic Research) Igor Ustinov
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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