CVE-2026-7426: CWE-787: Out-of-bounds Write in AWS FreeRTOS-Plus-TCP
Insufficient validation of the prefix length field in IPv6 Router Advertisement processing in FreeRTOS-Plus-TCP before V4.2.6 and V4.4.1 allows an adjacent network actor to cause memory corruption by sending a crafted Router Advertisement with a prefix length value exceeding the maximum valid length, resulting in a heap buffer overflow. Users processing IPv4 RA only are not impacted. To mitigate this issue, users should upgrade to the fixed version when available.
AI Analysis
Technical Summary
This vulnerability (CWE-787: Out-of-bounds Write) exists in FreeRTOS-Plus-TCP's IPv6 Router Advertisement processing before versions 4.2.6 and 4.4.1. The prefix length field is not properly validated, enabling an adjacent attacker to send a crafted Router Advertisement with a prefix length exceeding the maximum valid length. This leads to heap buffer overflow and memory corruption. IPv4-only RA processing is not impacted. The CVSS v3.1 score is 8.1, reflecting high impact on integrity and availability with low attack complexity and no privileges required. AWS provides a patch and manages remediation for this cloud service.
Potential Impact
Successful exploitation can cause heap buffer overflow resulting in memory corruption, impacting the integrity and availability of the affected system. The vulnerability requires an adjacent attacker and does not require user interaction or privileges. IPv4-only RA processing is not affected. There are no known exploits in the wild at this time.
Mitigation Recommendations
A patch is available from AWS in fixed versions 4.2.6 and 4.4.1 of FreeRTOS-Plus-TCP. Users should upgrade to these versions to remediate the vulnerability. Since this is a cloud-hosted service, AWS manages remediation on their side; users should consult the AWS security bulletin at https://aws.amazon.com/security/security-bulletins/2026-023-aws/ for the latest guidance and confirm patch application.
CVE-2026-7426: CWE-787: Out-of-bounds Write in AWS FreeRTOS-Plus-TCP
Description
Insufficient validation of the prefix length field in IPv6 Router Advertisement processing in FreeRTOS-Plus-TCP before V4.2.6 and V4.4.1 allows an adjacent network actor to cause memory corruption by sending a crafted Router Advertisement with a prefix length value exceeding the maximum valid length, resulting in a heap buffer overflow. Users processing IPv4 RA only are not impacted. To mitigate this issue, users should upgrade to the fixed version when available.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CWE-787: Out-of-bounds Write) exists in FreeRTOS-Plus-TCP's IPv6 Router Advertisement processing before versions 4.2.6 and 4.4.1. The prefix length field is not properly validated, enabling an adjacent attacker to send a crafted Router Advertisement with a prefix length exceeding the maximum valid length. This leads to heap buffer overflow and memory corruption. IPv4-only RA processing is not impacted. The CVSS v3.1 score is 8.1, reflecting high impact on integrity and availability with low attack complexity and no privileges required. AWS provides a patch and manages remediation for this cloud service.
Potential Impact
Successful exploitation can cause heap buffer overflow resulting in memory corruption, impacting the integrity and availability of the affected system. The vulnerability requires an adjacent attacker and does not require user interaction or privileges. IPv4-only RA processing is not affected. There are no known exploits in the wild at this time.
Mitigation Recommendations
A patch is available from AWS in fixed versions 4.2.6 and 4.4.1 of FreeRTOS-Plus-TCP. Users should upgrade to these versions to remediate the vulnerability. Since this is a cloud-hosted service, AWS manages remediation on their side; users should consult the AWS security bulletin at https://aws.amazon.com/security/security-bulletins/2026-023-aws/ for the latest guidance and confirm patch application.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- AMZN
- Date Reserved
- 2026-04-29T14:27:53.201Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
- Is Cloud Service
- true
- Vendor Advisory Urls
- [{"url":"https://aws.amazon.com/security/security-bulletins/2026-023-aws/","vendor":"AWS"}]
Threat ID: 69f25db7cbff5d8610434834
Added to database: 4/29/2026, 7:36:23 PM
Last enriched: 4/29/2026, 7:51:26 PM
Last updated: 4/29/2026, 8:45:25 PM
Views: 6
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