What is CVE-2026-5190?

CVE-2026-5190 is a high-severity vulnerability in AWS Aws-C-Event-Stream, classified under Out-of-bounds Write. CVSS score: 7.5/10. Published 2026-03-31.

How severe is CVE-2026-5190?

High severity. CVSS v3 base score is 7.5 out of 10.

Buffer overflow in AWS Aws-C-Event-Stream

CVE-2026-5190

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.

Vulnerability class: Buffer Overflow

EPSS: 0.004 (30.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H.

Affected products

Aws Aws-c-event-stream — versions 0.6.0

Weakness classification (CWE)

CWE-787 — Out-of-bounds Write

References

ff89ba41-3aa1-4d27-914a-91399e9639e5 (vendor-advisory)
ff89ba41-3aa1-4d27-914a-91399e9639e5 (third-party-advisory)
ff89ba41-3aa1-4d27-914a-91399e9639e5 (patch)

Frequently asked questions

What is CVE-2026-5190?: CVE-2026-5190 is a high-severity vulnerability in AWS Aws-C-Event-Stream, classified under Out-of-bounds Write. CVSS score: 7.5/10. Published 2026-03-31.
How severe is CVE-2026-5190?: High severity. CVSS v3 base score is 7.5 out of 10.