CVE-2026-54290 — Hono: CORS Middleware reflects any Origin with credentials when `origin` defaults to the wildcard

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.25, with credentials: true and no explicit origin (the default wildcard), the CORS Middleware reflects the request's Origin and sends Access-Control-Allow-Credentials: true. Any site can then make credentialed cross-origin requests and read the responses, exposing cookie-authenticated endpoints to arbitrary origins. This vulnerability is fixed in 4.12.25.

Published Jun 22, 2026Updated Jun 22, 2026Sources: cvelistV5, GitHub_M

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.

Exploitation

Unreported

no source claims exploitation

EPSS

chance of exploitation in 30 days

Affects

honojs

hono

CVSS base

7.1

HIGH

CISA SSVC assessment

Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.

CISA

Exploitation

None

none · proof-of-concept · active

Automatable

can an attacker script all four kill-chain steps

Technical impact

Partial

partial · total control of the vulnerable component

Affected scope

The catalog records vendors and products as separate lists, not pairs, so which product belongs to which vendor is not something this page can say.

Vendors (1)

honojs

Products (1)

hono

Every base score collected

Sources score independently and disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Source
7.1	CVSS 3.1	HIGH	—	—	cvelistV5

Weakness & attack patterns

CWE-942

References

1 on the record

github.com/honojs/hono/security/advisories/GHSA-88fw-hqm2-52qc
x_refsource_CONFIRM

Elsewhere on this site

honojsevery CVE for this vendor
CWE-942other pages naming this weakness

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.