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Advisory details: vulnrichment / CVE-2026-42583
Advisory ID vulnrichment/CVE-2026-42583
Aliases
Summary Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, Lz4FrameDecoder allocates a ByteBuf of size decompressedLength (up to 32 MB per block) before LZ4 runs. A peer only needs a 21-byte header plus compressedLength payload bytes - 22 bytes if compressedLength == 1 - to force that allocation. This vulnerability is fixed in 4.2.13.Final and 4.1.133.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 (2)
CWE-770 Allocation of Resources Without Limits or Throttling
CWE-400 Uncontrolled Resource Consumption
System Score Found at
cvssv3.1 7.5
ssvc Track
Reference id Reference type URL
GHSA-mj4r-2hfc-f8p6 Other https://github.com/netty/netty/security/advisories/GHSA-mj4r-2hfc-f8p6
No exploits are available.

No EPSS data available for this advisory.

Patch URL
There are no known patches.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Found at None
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: SSVCv2/E:P/A:Y/T:P/P:M/B:A/M:M/D:T/2026-05-14T15:40:38Z/ Found at None

Vector: SSVCv2/E:P/A:Y/T:P/P:M/B:A/M:M/D:T/2026-05-14T15:40:38Z/

Decision: Track

Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2026/42xxx/CVE-2026-42583.json

Source Advisory: vulnrichment/CVE-2026-42583

View SSVC decision tree 
[{'Exploitation': 'poc'},
 {'Automatable': 'yes'},
 {'Technical Impact': 'partial'},
 {'Mission Prevalence': 'minimal'},
 {'Public Well-being Impact': 'material'},
 {'Mission & Well-being': 'medium'}]