7.5 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
0.002 Low
EPSS
Percentile
53.4%
An attacker can send an invalid Content-Type
header that can cause the application to crash, leading to a possible Denial of Service attack. Only the v4.x line is affected.
(This was updated: upon a close inspection, v3.x is not affected after all).
Yes, update to > v4.8.0
.
You can reject the malicious content types before the body parser enters in action.
const badNames = Object.getOwnPropertyNames({}.__proto__)
fastify.addHook('onRequest', async (req, reply) => {
for (const badName of badNames) {
if (req.headers['content-type'].indexOf(badName) > -1) {
reply.code(415)
throw new Error('Content type not supported')
}
}
})
See the HackerOne report #1715536