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TI-2026-82700 Aliases CVE-2026-118769

Botan C API block size truncation can cause memory corruption

Priority MEDIUM 42CWE-125Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 3 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-787 and the CVSS impact.

Summary

Botan versions from 2.1.0 before 3.13.0 contain an integer conversion flaw (CWE-681) in the C API function botan_block_cipher_block_size, which converts a size_t block size to int without a bounds check. In an application that accepts external algorithm parameter strings and uses the FFI raw ECB mode, an unauthenticated attacker can select the variable-block-size Lion cipher so the reported size is truncated. The caller then allocates too little memory, and later block processing causes memory corruption. The C++ API and common C API modes such as CBC and CTR are not affected.

Written with Claude Haiku 5.5 from the sources below · 2026-11-03

Description from the CNA

Botan is a C++ cryptography library. From 2.1.0 until 3.13.0, the Botan C API function botan_block_cipher_block_size converted a size_t block size to int without a bounds check. In an application that accepts external algorithm parameter strings and uses the FFI raw ECB mode, an attacker can select the variable-block-size Lion cipher so that the reported size is truncated, the caller allocates insufficient memory, and later block processing causes memory corruption. The C++ API and normally used C API modes such as CBC and CTR are unaffected. This issue is fixed in version 3.13.0.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00365 30th percentileScored 2026-11-07
Fix Partial botan (randombit): 3.13.0Red Hat: 3 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

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

Affected products

VendorProductAffected versionsFixed inStatusSource
randombitbotan2.1.0 to before 3.13.03.13.0Patch availableCNA
  • botan Vendorrandombit Affected 2.1.0 to before 3.13.0 Fixed in 3.13.0 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:botan_project:botan:*:*:*:*:*:*:*:*——randombit
  • cpe:2.3:a:botan_project:botan:*:*:*:*:*:*:*:* Versions — — ·randombit

Remediation

Upgrade Botan to version 3.13.0 or later. The sources list no fixed version for Red Hat Ansible Automation Platform 2, Red Hat Enterprise Linux 10 and Red Hat Enterprise Linux 9, and no fix plan is available for them.

Written with Claude Haiku 5.5 from the sources below · 2026-11-03

  • Fix · CNA botan (randombit) Fixed in 3.13.0

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Ansible Automation Platform 2AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred
Not affected: 1 product
  • Red Hat Hardened Images

Timeline

  1. 2026-10-29 Threatist record created from CVE-2026-118769
  2. 2026-10-29 CISA SSVC decision points changed
  3. 2026-10-29 Priority changed: MEDIUM → LOW
  4. 2026-10-31 Priority changed: LOW → MEDIUM
  5. 2026-11-03 Affected versions changed · Red Hat
  6. 2026-11-03 CVSS score added · Red Hat

References

Other 3

  • 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 43 →

Sources

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