CVE-2019-17638
Operation on a Resource after Expiration or Release in Jetty Server
Description
In Eclipse Jetty, versions 9.4.27.v20200227 to 9.4.29.v20200521, in case of too large response headers, Jetty throws an exception to produce an HTTP 431 error. When this happens, the ByteBuffer containing the HTTP response headers is released back to the ByteBufferPool twice. Because of this double release, two threads can acquire the same ByteBuffer from the pool and while thread1 is about to use the ByteBuffer to write response1 data, thread2 fills the ByteBuffer with other data. Thread1 then proceeds to write the buffer that now contains different data. This results in client1, which issued request1 seeing data from another request or response which could contain sensitive data belonging to client2 (HTTP session ids, authentication credentials, etc.). If the Jetty version cannot be upgraded, the vulnerability can be significantly reduced by configuring a responseHeaderSize significantly larger than the requestHeaderSize (12KB responseHeaderSize and 8KB requestHeaderSize).
How to fix CVE-2019-17638
To remediate CVE-2019-17638, upgrade the affected package to a fixed version below.
- —upgrade to 9.4.31-1 or later
- —upgrade to 9.4.30.v20200611 or later
Is CVE-2019-17638 being exploited?
Moderate — EPSS is 30.9%. Track this CVE but it's not at the top of the prioritisation list.
Affected packages (2)
- from 0, < 9.4.31-1
- >= 9.4.27, < 9.4.30.v20200611
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | CRITICAL9.4 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L |