VulnerabilityModified
CVE-2026-33870
Netty is an asynchronous, event-driven network application framework.
HIGH 7.5EPSS 0.64%
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.64%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Netty is an asynchronous, event-driven network application framework. In versions prior to 4.1.132.Final and 4.2.10.Final, Netty incorrectly parses quoted strings in HTTP/1.1 chunked transfer encoding extension values, enabling request smuggling attacks. Versions 4.1.132.Final and 4.2.10.Final fix the issue.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- EPSS
- 0.64% probability · 49th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-444
- Affected
- netty/netty
- Source
- security-advisories@github.com
References
- https://github.com/netty/netty/security/advisories/GHSA-pwqr-wmgm-9rr8Exploit, Mitigation, Vendor Advisory
- https://w4ke.info/2025/06/18/funky-chunks.htmlTechnical Description
- https://w4ke.info/2025/10/29/funky-chunks-2.htmlTechnical Description
- https://www.rfc-editor.org/rfc/rfc9110Technical Description
- https://access.redhat.com/errata/RHSA-2026:10175
- https://access.redhat.com/errata/RHSA-2026:10184
- https://access.redhat.com/errata/RHSA-2026:13571
- https://access.redhat.com/errata/RHSA-2026:14272
- https://access.redhat.com/errata/RHSA-2026:14276
- https://access.redhat.com/errata/RHSA-2026:17668
- https://access.redhat.com/errata/RHSA-2026:17789
- https://access.redhat.com/errata/RHSA-2026:18054
- https://access.redhat.com/errata/RHSA-2026:18055
- https://access.redhat.com/errata/RHSA-2026:18059
- https://access.redhat.com/errata/RHSA-2026:22619
- https://access.redhat.com/errata/RHSA-2026:34608
- https://access.redhat.com/errata/RHSA-2026:65126
- https://access.redhat.com/errata/RHSA-2026:7109
- https://access.redhat.com/errata/RHSA-2026:7380
- https://access.redhat.com/errata/RHSA-2026:8159
- https://access.redhat.com/errata/RHSA-2026:8509
- https://access.redhat.com/security/cve/CVE-2026-33870
- https://bugzilla.redhat.com/show_bug.cgi?id=2452453
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33870.json
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.