What is CVE-2026-59897?

CVE-2026-59897 is a medium-severity vulnerability in Honojs Hono, classified under CWE-348. CVSS score: 4.8/10. Published 2026-07-08.

How severe is CVE-2026-59897?

Medium severity. CVSS v3 base score is 4.8 out of 10.

Vulnerability in Honojs Hono

CVE-2026-59897

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.3.3 before 4.12.27, the AWS API Gateway v1 adapter can drop a distinct repeated request header value because it de-duplicates values using a subst…

CVSS v3 metric

CVSS v3 base score 4.8 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N.

Affected products

Honojs Hono — versions >= 4.3.3, < 4.12.27

Weakness classification (CWE)

CWE-348

References

security-advisories@github.com (x_refsource_CONFIRM)
security-advisories@github.com (x_refsource_MISC)
security-advisories@github.com (x_refsource_MISC)

Frequently asked questions

What is CVE-2026-59897?: CVE-2026-59897 is a medium-severity vulnerability in Honojs Hono, classified under CWE-348. CVSS score: 4.8/10. Published 2026-07-08.
How severe is CVE-2026-59897?: Medium severity. CVSS v3 base score is 4.8 out of 10.