CVE-2026-102566: Out-of-bounds Write in OpenNMT CTranslate2
CTranslate2 before 4.8.1 contains a heap-based buffer overflow in the binary model loader that fails to validate payload length against allocated buffer size. Attackers can craft malicious model files with oversized payload lengths to write past heap allocation boundaries, causing crashes or arbitrary code execution.
AI Analysis
Technical Summary
CVE-2026-102566 is a heap-based buffer overflow vulnerability in OpenNMT's CTranslate2 library prior to version 4.8.1. The flaw exists in the binary model loader component, which fails to validate that the payload length fits within the allocated buffer size. An attacker can exploit this by supplying a malicious model file with an oversized payload length, leading to writes beyond the heap allocation boundary. This can result in denial of service via crashes or potentially allow arbitrary code execution.
Potential Impact
Successful exploitation can cause the application to crash or enable arbitrary code execution, which may lead to compromise of the host running the vulnerable CTranslate2 version. The vulnerability requires local access (AV:L) and user interaction (UI:P), with no privileges required (PR:N). The CVSS 4.0 base score is 8.5 (high severity), reflecting the significant impact on confidentiality, integrity, and availability.
Mitigation Recommendations
Upgrade to CTranslate2 version 4.8.1 or later, where this heap-based buffer overflow vulnerability has been fixed. Patch status is confirmed by the version range affected and the fixed version 4.8.1. No other mitigations are indicated.
CVE-2026-102566: Out-of-bounds Write in OpenNMT CTranslate2
Description
CTranslate2 before 4.8.1 contains a heap-based buffer overflow in the binary model loader that fails to validate payload length against allocated buffer size. Attackers can craft malicious model files with oversized payload lengths to write past heap allocation boundaries, causing crashes or arbitrary code execution.
CVSS v4.0
Score 8.5high
Affected software
OpenNMT
CTranslate2
pkg:github/opennmt/CTranslate2Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-102566 is a heap-based buffer overflow vulnerability in OpenNMT's CTranslate2 library prior to version 4.8.1. The flaw exists in the binary model loader component, which fails to validate that the payload length fits within the allocated buffer size. An attacker can exploit this by supplying a malicious model file with an oversized payload length, leading to writes beyond the heap allocation boundary. This can result in denial of service via crashes or potentially allow arbitrary code execution.
Potential Impact
Successful exploitation can cause the application to crash or enable arbitrary code execution, which may lead to compromise of the host running the vulnerable CTranslate2 version. The vulnerability requires local access (AV:L) and user interaction (UI:P), with no privileges required (PR:N). The CVSS 4.0 base score is 8.5 (high severity), reflecting the significant impact on confidentiality, integrity, and availability.
Mitigation Recommendations
Upgrade to CTranslate2 version 4.8.1 or later, where this heap-based buffer overflow vulnerability has been fixed. Patch status is confirmed by the version range affected and the fixed version 4.8.1. No other mitigations are indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-09-29T13:43:06.440Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6abbcfbdf7a7c5410683e20b
Added to database: 09/29/2026, 14:48:29 UTC
Last enriched: 09/29/2026, 15:02:51 UTC
Last updated: 09/29/2026, 18:00:32 UTC
Views: 11
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