CVE-2026-44375: CWE-789: Memory Allocation with Excessive Size Value in AArnott Nerdbank.MessagePack
Nerdbank. MessagePack versions prior to 1. 1. 62 contain a vulnerability in the DateTime decoding functionality where an attacker can supply a malicious MessagePack payload with an oversized timestamp extension length. This causes the library to allocate an attacker-controlled amount of memory on the stack, leading to a StackOverflowException that terminates the process and cannot be caught by user code. The issue is fixed in version 1. 1. 62. The vulnerability has a CVSS score of 7. 5, indicating high severity, and impacts availability without affecting confidentiality or integrity.
AI Analysis
Technical Summary
CVE-2026-44375 describes a stack allocation vulnerability in the Nerdbank.MessagePack serialization library before version 1.1.62. Specifically, during DateTime decoding, the library does not properly control the size of the timestamp extension length declared in a MessagePack payload. This allows an attacker to cause the reader to allocate an excessive number of bytes on the stack, triggering a StackOverflowException that forcibly terminates the process. This vulnerability is classified under CWE-789 (Memory Allocation with Excessive Size Value). The vulnerability is resolved in version 1.1.62.
Potential Impact
Exploitation of this vulnerability results in a denial of service by causing the application process to terminate unexpectedly due to an uncatchable StackOverflowException. There is no impact on confidentiality or integrity according to the CVSS vector. No known exploits are reported in the wild at this time.
Mitigation Recommendations
Upgrade Nerdbank.MessagePack to version 1.1.62 or later, where this vulnerability is fixed. No other official remediation or temporary fixes are indicated. Patch status is not explicitly stated in the vendor advisory, but the description confirms the issue is resolved in 1.1.62.
CVE-2026-44375: CWE-789: Memory Allocation with Excessive Size Value in AArnott Nerdbank.MessagePack
Description
Nerdbank. MessagePack versions prior to 1. 1. 62 contain a vulnerability in the DateTime decoding functionality where an attacker can supply a malicious MessagePack payload with an oversized timestamp extension length. This causes the library to allocate an attacker-controlled amount of memory on the stack, leading to a StackOverflowException that terminates the process and cannot be caught by user code. The issue is fixed in version 1. 1. 62. The vulnerability has a CVSS score of 7. 5, indicating high severity, and impacts availability without affecting confidentiality or integrity.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-44375 describes a stack allocation vulnerability in the Nerdbank.MessagePack serialization library before version 1.1.62. Specifically, during DateTime decoding, the library does not properly control the size of the timestamp extension length declared in a MessagePack payload. This allows an attacker to cause the reader to allocate an excessive number of bytes on the stack, triggering a StackOverflowException that forcibly terminates the process. This vulnerability is classified under CWE-789 (Memory Allocation with Excessive Size Value). The vulnerability is resolved in version 1.1.62.
Potential Impact
Exploitation of this vulnerability results in a denial of service by causing the application process to terminate unexpectedly due to an uncatchable StackOverflowException. There is no impact on confidentiality or integrity according to the CVSS vector. No known exploits are reported in the wild at this time.
Mitigation Recommendations
Upgrade Nerdbank.MessagePack to version 1.1.62 or later, where this vulnerability is fixed. No other official remediation or temporary fixes are indicated. Patch status is not explicitly stated in the vendor advisory, but the description confirms the issue is resolved in 1.1.62.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-05-05T20:15:20.631Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a05e888ec166c07b0eee36c
Added to database: 5/14/2026, 3:21:44 PM
Last enriched: 5/14/2026, 3:36:50 PM
Last updated: 5/14/2026, 4:36:08 PM
Views: 2
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