CVE-2026-107296 (GCVE-0-2026-107296)

Vulnerability from cvelistv5 – Published: 2026-10-08 17:05 – Updated: 2026-10-14 01:01
VLAI
Title
msgpack5: Decoding negative int64 values mutates the input buffer
Summary
msgpack5 is a msgpack v5 implementation for node.js and the browser. Prior to 6.1.0, decoding a negative signed 64-bit integer modifies the corresponding bytes in the caller-provided input buffer while computing the value. Applications that retain or reuse encoded input for integrity checks, logging, or later processing can observe silently corrupted data, while positive integers and other MessagePack value types are unaffected. This issue is fixed in version 6.1.0.
Severity
3.7 (Low)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-14 01:01 UTC
CWE
  • CWE-471 - Modification of Assumed-Immutable Data (MAID)
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7670 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
mcollina msgpack5 Affected: < 6.1.0
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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