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Advisory details: vulnrichment / CVE-2025-58056
Advisory ID vulnrichment/CVE-2025-58056
Aliases
Summary Netty is an asynchronous event-driven network application framework for development of maintainable high performance protocol servers and clients. In versions 4.1.124.Final, and 4.2.0.Alpha3 through 4.2.4.Final, Netty incorrectly accepts standalone newline characters (LF) as a chunk-size line terminator, regardless of a preceding carriage return (CR), instead of requiring CRLF per HTTP/1.1 standards. When combined with reverse proxies that parse LF differently (treating it as part of the chunk extension), attackers can craft requests that the proxy sees as one request but Netty processes as two, enabling request smuggling attacks. This is fixed in versions 4.1.125.Final and 4.2.5.Final.
Status Published
Exploitability 0.5
Weighted Severity 0.0
Risk
Affected and Fixed Packages Package Details
Introduced and Fixed Package Commit Patches Package Commit Patches Details
Weaknesses (1)
CWE-444 Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
System Score Found at
cvssv4 2.9
ssvc Track
Reference id Reference type URL
https://datatracker.ietf.org/doc/html/rfc9112#name-chunked-transfer-coding
https://github.com/JLLeitschuh/unCVEed/issues/1
https://github.com/netty/netty/commit/edb55fd8e0a3bcbd85881e423464f585183d1284
https://github.com/netty/netty/issues/15522
https://github.com/netty/netty/pull/15611
https://w4ke.info/2025/06/18/funky-chunks.html
GHSA-fghv-69vj-qj49 https://github.com/netty/netty/security/advisories/GHSA-fghv-69vj-qj49
No exploits are available.

No EPSS data available for this advisory.

Patch URL
There are no known patches.
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P Found at None
Attack Vector (AV) Attack Complexity (AC) Attack Requirements (AT) Privileges Required (PR) User Interaction (UI) Vulnerable System Impact Confidentiality (VC) Vulnerable System Impact Integrity (VI) Vulnerable System Impact Availability (VA) Subsequent System Impact Confidentiality (SC) Subsequent System Impact Integrity (SI) Subsequent System Impact Availability (SA)

network

adjacent

local

physical

low

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none

present

none

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high

none

passive

active

high

low

none

high

low

none

high

low

none

high

low

none

high

low

none

high

low

none
Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2025-09-04T19:09:52Z/ Found at None

Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2025-09-04T19:09:52Z/

Decision: Track

Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2025/58xxx/CVE-2025-58056.json

Source Advisory: vulnrichment/CVE-2025-58056

View SSVC decision tree 
[{'Exploitation': 'none'},
 {'Automatable': 'no'},
 {'Technical Impact': 'partial'},
 {'Mission Prevalence': 'minimal'},
 {'Public Well-being Impact': 'material'},
 {'Mission & Well-being': 'medium'}]