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 DateTime decoding where a malicious MessagePack payload can specify an excessively large timestamp extension length. This causes the reader to allocate a large 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 high severity with a CVSS score of 7. 5 and does not impact confidentiality or integrity but results in denial of service through application crash.
AI Analysis
Technical Summary
CVE-2026-44375 is a vulnerability in the Nerdbank.MessagePack serialization library (versions before 1.1.62) involving uncontrolled stack allocation during DateTime decoding. A crafted MessagePack payload can declare an oversized timestamp extension length, causing the library to allocate an attacker-controlled number of bytes on the stack. This triggers a StackOverflowException that terminates the process and cannot be handled by user code. The vulnerability is classified under CWE-789 (Memory Allocation with Excessive Size Value) and is fixed in version 1.1.62.
Potential Impact
The vulnerability allows an attacker to cause a denial of service by crashing the application process via an uncatchable StackOverflowException. There is no impact on data confidentiality or integrity. 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. Since the vendor advisory does not provide additional remediation details, applying this official fix is the recommended action. Patch status is confirmed by the vendor stating the issue is fixed 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 DateTime decoding where a malicious MessagePack payload can specify an excessively large timestamp extension length. This causes the reader to allocate a large 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 high severity with a CVSS score of 7. 5 and does not impact confidentiality or integrity but results in denial of service through application crash.
CVSS v3.1
Score 7.5high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-44375 is a vulnerability in the Nerdbank.MessagePack serialization library (versions before 1.1.62) involving uncontrolled stack allocation during DateTime decoding. A crafted MessagePack payload can declare an oversized timestamp extension length, causing the library to allocate an attacker-controlled number of bytes on the stack. This triggers a StackOverflowException that terminates the process and cannot be handled by user code. The vulnerability is classified under CWE-789 (Memory Allocation with Excessive Size Value) and is fixed in version 1.1.62.
Potential Impact
The vulnerability allows an attacker to cause a denial of service by crashing the application process via an uncatchable StackOverflowException. There is no impact on data confidentiality or integrity. 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. Since the vendor advisory does not provide additional remediation details, applying this official fix is the recommended action. Patch status is confirmed by the vendor stating the issue is fixed 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: 5/21/2026, 3:45:33 PM
Last updated: 6/3/2026, 5:09:04 PM
Views: 50
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