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TI-2026-25336 Aliases CVE-2026-32877

Botan: Heap Buffer Over-read in SM2 Decryption via Undersized C3 Hash Field

Priority MEDIUM 41CWE-125Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
Low · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00289 21st percentileScored 2026-11-07
Fix Fixed botan (randombit): 3.11.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
randombitbotan2.3.0 to before 3.11.03.11.0Patch availableCNA
  • botan Vendorrandombit Affected 2.3.0 to before 3.11.0 Fixed in 3.11.0 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:botan_project:botan:*:*:*:*:*:*:*:*2.3.0 to before 3.11.0Vulnerablerandombit
  • cpe:2.3:a:botan_project:botan:*:*:*:*:*:*:*:* Versions 2.3.0 to before 3.11.0 Vulnerable ·randombit

Remediation

  • Fix · CNA botan (randombit) Fixed in 3.11.0

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat Enterprise Linux 10

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-32877

References

Advisory 1

  • TI-2024-33818 Botan before 3.6.0, when certain GCC versions are used, has a compiler-induced… CVSS 3.1MEDIUM 5.9
  • TI-2024-33817 Botan before 3.6.0, when certain LLVM versions are used, has compiler-induced… CVSS 3.1MEDIUM 5.9
  • TI-2016-02004 Integer overflow in the PointGFp constructor in Botan before 1.10.11 and 1.11.x before… CVSS 3.0CRITICAL 9.8
  • TI-2016-02005 Heap-based buffer overflow in the P-521 reduction function in Botan 1.11.x before 1.11.27… CVSS 3.0CRITICAL 9.8
  • TI-2026-26828 Botan has a certificate authentication bypass due to trust anchor confusion CVSS 4.0CRITICAL 9.3
  • TI-2016-07479 In Botan 1.8.0 through 1.11.33, when decoding BER data an integer overflow could occur… CVSS 3.0CRITICAL 9.8
See all 34 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences