CVE-2019-17638

CRITICAL

Eclipse Jetty <9.4.29 - Use After Free

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2019-17638. PoCs published by forse01.

AI-analyzed exploit summary The repository contains no actual exploit code for CVE-2019-17638. Instead, it includes a script that downloads an external tool from Synopsys and configuration files for Jetty, which are not related to exploiting the vulnerability.

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).

Exploits (1)

nomisec SUSPICIOUS 1 stars
by forse01 · poc
https://github.com/forse01/CVE-2019-17638-Jetty

The repository contains no actual exploit code for CVE-2019-17638. Instead, it includes a script that downloads an external tool from Synopsys and configuration files for Jetty, which are not related to exploiting the vulnerability.

Classification
Suspicious 90%
Attack Type
Other
Complexity
Trivial
Reliability
Theoretical
Target: Jetty
No auth needed
devstral-2 · analyzed Feb 19, 2026 Full analysis →

References (17)

Core 17
Core References
Vendor Advisory x_refsource_confirm
https://bugs.eclipse.org/bugs/show_bug.cgi?id=564984
Mailing List mailing-list x_refsource_mlist
http://www.openwall.com/lists/oss-security/2020/08/17/1

Scores

CVSS v3 9.4
EPSS 0.3093
EPSS Percentile 96.9%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L

Details

CWE
CWE-675 CWE-672
Status published
Products (4)
eclipse/jetty 9.4.27 20200227
eclipse/jetty 9.4.28 20200408
eclipse/jetty 9.4.29 20200521
org.eclipse.jetty/jetty-server 9.4.27 - 9.4.30.v20200611Maven
Published Jul 09, 2020
Tracked Since Feb 18, 2026