CVE-2026-59901CWE-835

CVE-2026-59901

High · published July 29, 2026

CVSS v3.1
7.5
EPSS
0%
Percentile
38.9
In the wild
Unconfirmed
What it is

Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.136.Final and 4.2.16.Final, the `Bzip2Decoder` handler in Netty's compression codec pipeline is vulnerable to a denial-of-service attack through a malformed bzip2 stream that permanently captures the event-loop thread in an infinite loop. The vulnerability exists in the run-length encoding (RLE) state machine within [`Bzip2BlockDecompressor.read()`]. This issue has been fixed in versions 4.1.136.Final and 4.2.16.Final.

The record
Technical detail
CVSS v3.1
7.5 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00460 · 38.9th percentile
Weakness
CWE-835 · Loop with Unreachable Exit Condition ('Infinite Loop')
Published
2026-07-29T22:16Z
Affected products (2)
ProductVersionsFixed in
netty/netty< 4.1.1364.1.136
netty/netty≥ 4.2.0, < 4.2.164.2.16
References (1)
https://github.com/netty/netty/security/advisories/GHSA-558v-64gr-wgg4 · [email protected]
EPSS history
Timeline
  • 29 JUL 17:48Z
    Netty Bzip2Decoder: Infinite Loop in RLE State Machine Leads to Event-Loop Thread Hang
    cvelistv5