CVE-2025-67735 | Netty has a CRLF Injection vulnerability in io.netty.handler.codec.http.HttpRequestEncoder

Exp

Netty is an asynchronous, event-driven network application framework. In versions prior to 4.1.129.Final and 4.2.8.Final, the `io.netty.handler.codec.http.HttpRequestEncoder` has a CRLF injection with the request URI when constructing a request. This leads to request smuggling when `HttpRequestEncoder` is used without proper sanitization of the URI. Any application / framework using `HttpRequestEncoder` can be subject to be abused to perform request smuggling using CRLF injection. Versions 4.1.129.Final and 4.2.8.Final fix the issue.

Published: 2025-12-15 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-67735 is rated Exploit Available (50/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.29%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2025-67735

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2025-67735

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.02% 0.29% +0.27%
2 2026-01-24 0.05% 0.02% -0.03%
3 2025-12-22 — 0.05% —

Full EPSS history (4 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-67735

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 2.5 [email protected]

Weakness enumeration for CVE-2025-67735

GitHub Security Advisory for CVE-2025-67735

GHSA-84h7-rjj3-6jx4 · Severity: medium · Ecosystem: maven — Netty has a CRLF Injection vulnerability in io.netty.handler.codec.http.HttpRequestEncoder

OS Trackers for CVE-2025-67735

vendor priority summary link
debian not yet assigned CVE-2025-67735 not yet assigned priority: Debian including 1 source packages (netty), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2025-67735
redhat medium — https://access.redhat.com/security/cve/CVE-2025-67735
suse medium CVE-2025-67735 severity moderate: SUSE including 9 source package names (5.1.2.8.13.2:netty-4.1.130-150200.4.40.1, netty-4.1.130-1.1, …), 29 product×package rows across 22 product lines (Container suse/multi-linux-manager/5.1/x86_64/server, Image server-image, … (22 product lines)): Known Not Affected 19, Fixed 10. https://www.suse.com/security/cve/CVE-2025-67735/
ubuntu medium CVE-2025-67735 medium priority: Ubuntu including 1 source packages (netty), 9 status rows across 9 suites (bionic, focal, jammy, noble, plucky, questing, trusty, upstream, xenial): needs-triage 8, ignored 1. https://ubuntu.com/security/CVE-2025-67735

Affected software / configurations for CVE-2025-67735

Vendor Product Version Raw CPE
netty netty < 4.1.129 cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*
netty netty >= 4.2.0, < 4.2.8 cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*

References for CVE-2025-67735

cvelogic Threat Intelligence