CVE-2026-32877
Received Received - Intake
Heap Over-Read in Botan SM2 Decryption Causes Crash

Publication date: 2026-03-30

Last updated on: 2026-04-13

Assigner: GitHub, Inc.

Description
Botan is a C++ cryptography library. From version 2.3.0 to before version 3.11.0, during SM2 decryption, the code that checked the authentication code value (C3) failed to check that the encoded value was of the expected length prior to comparison. An invalid ciphertext can cause a heap over-read of up to 31 bytes, resulting in a crash or potentially other undefined behavior. This issue has been patched in version 3.11.0.
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Meta Information
Published
2026-03-30
Last Modified
2026-04-13
Generated
2026-06-16
AI Q&A
2026-03-31
EPSS Evaluated
2026-06-15
NVD
CVE-2026-32877
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
botan_project botan From 2.3.0 (inc) to 3.11.0 (exc)
Helpful Resources
Exploitability
CWE
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KEV
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CWE ID Description
CWE-125 The product reads data past the end, or before the beginning, of the intended buffer.
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Executive Summary

This vulnerability exists in the Botan C++ cryptography library versions from 2.3.0 up to but not including 3.11.0. During the SM2 decryption process, the code responsible for checking the authentication code value (C3) did not verify that the encoded value was of the expected length before performing the comparison. This flaw allows an invalid ciphertext to trigger a heap over-read of up to 31 bytes, which can cause the program to crash or exhibit other undefined behaviors.

Impact Analysis

The vulnerability can lead to a heap over-read during SM2 decryption, which may cause the application using the Botan library to crash or behave unpredictably. This can result in denial of service or potentially other undefined behaviors that could be exploited depending on the context in which the library is used.

Mitigation Strategies

To mitigate this vulnerability, you should upgrade the Botan cryptography library to version 3.11.0 or later, where the issue has been patched.

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