Client code execution via crafted event-stream headers
Published Mar 31, 2026 · Updated Mar 31, 2026
Out-of-bounds write in the AWS aws-c-event-stream decoder before 0.6.0 allows remote attackers to execute code on client applications. While parsing crafted event-stream headers, the streaming decoder writes beyond a memory buffer and corrupts client-process memory. Exploitation requires the client to connect to an attacker-controlled server and process its specially formatted message; AWS service endpoints are not affected.
Summary
What happened
Out-of-bounds write in the AWS aws-c-event-stream decoder before 0.6.0 allows remote attackers to execute code on client applications. While parsing crafted event-stream headers, the streaming decoder writes beyond a memory buffer and corrupts client-process memory. Exploitation requires the client to connect to an attacker-controlled server and process its specially formatted message; AWS service endpoints are not affected.
The record
- CVE
- CVE-2026-5190
- Published
- Mar 31, 2026
- Updated
- Mar 31, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-787, CAPEC-100, T1203
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Mar 31, 2026CVE publishedPublication date reported by the CVE source.
- Mar 31, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What is affected?
Affected products and versions are unavailable in this record.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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