AWS aws-c-event-stream up to 0.5.x event-stream Message out-of-bounds write

CVSS Meta Temp Score
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CTI Interest Score
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6.1$0-$5k0.00

Summaryinfo

A vulnerability was found in AWS aws-c-event-stream up to 0.5.x. It has been classified as critical. This issue affects some unknown processing of the component event-stream Message Handler. This manipulation causes out-of-bounds write. This vulnerability is tracked as CVE-2026-5190. The attack is possible to be carried out remotely. No exploit exists. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability classified as critical was found in AWS aws-c-event-stream up to 0.5.x. Affected by this vulnerability is an unknown code block of the component event-stream Message Handler. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. The CWE definition for the vulnerability is CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

Out-of-bounds write in the streaming decoder component in aws-c-event-stream before 0.6.0 might allow a third party operating a server to cause memory corruption leading to arbitrary code execution on a client application that processes crafted event-stream messages. To remediate this issue, users should upgrade to version 0.6.0 or later.

The advisory is shared at aws.amazon.com. This vulnerability is known as CVE-2026-5190 since 03/30/2026. The exploitation appears to be difficult. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 305836 (openSUSE 16 Security Update : aws-c-event-stream (openSUSE-SU-2026:20477-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 0.6.0 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (305836). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.2
VulDB Meta Temp Score: 6.1

VulDB Base Score: 5.0
VulDB Temp Score: 4.8
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.5
CNA Vector (AMZN): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 305836
Nessus Name: openSUSE 16 Security Update : aws-c-event-stream (openSUSE-SU-2026:20477-1)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: aws-c-event-stream 0.6.0

Timelineinfo

03/30/2026 CVE reserved
03/31/2026 +1 days Advisory disclosed
03/31/2026 +0 days VulDB entry created
07/25/2026 +116 days VulDB entry last update

Sourcesinfo

Advisory: aws.amazon.com
Status: Confirmed

CVE: CVE-2026-5190 (🔒)
GCVE (CVE): GCVE-0-2026-5190
GCVE (VulDB): GCVE-100-354457

Entryinfo

Created: 03/31/2026 20:02
Updated: 07/25/2026 22:17
Changes: 03/31/2026 20:02 (76), 04/10/2026 17:15 (2), 07/25/2026 22:17 (1)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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