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Advisory details: gitlab / maven/io.netty/netty-codec-http/CVE-2026-55831
Advisory ID gitlab/maven/io.netty/netty-codec-http/CVE-2026-55831
Aliases CVE-2026-55831
GHSA-6jqx-86gh-f27w
Summary Netty SPDY SETTINGS frame count materializes unbounded settings map Netty's SPDY SETTINGS decoder accepts a peer-declared SETTINGS entry count up to the 24-bit frame-length limit and materializes every unique setting ID in `DefaultSpdySettingsFrame` without an implementation-level count cap. A remote SPDY/3.1 peer can send one syntactically valid roughly 2 MiB SETTINGS frame that creates 262144 map entries, amplifying network input into heap growth and ordered-map insertion work.
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 (3)
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 https://gitlab.com/gitlab-org/advisories-community/-/blob/main/maven/io.netty/netty-codec-http/CVE-2026-55831.yml
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/2026-07-23T14:33:23Z/

Decision: Track

Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2026/55xxx/CVE-2026-55831.json

Source Advisory: vulnrichment/CVE-2026-55831

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