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GHSA-f256-j965-7f32

MediumCVSS 5.9 / 10
Published Mar 30, 2021·Last modified Feb 4, 2026
Affected Components(0)

No affected components available

Description

Impact

The content-length header is not correctly validated if the request only use a single Http2HeaderFrame with the endStream set to to true. This could lead to request smuggling if the request is proxied to a remote peer and translated to HTTP/1.1

This is a followup of https://github.com/netty/netty/security/advisories/GHSA-wm47-8v5p-wjpj which did miss to fix this one case.

Patches

This was fixed as part of 4.1.61.Final

Workarounds

Validation can be done by the user before proxy the request by validating the header.

Risk Scores
Base Score
5.9

The vulnerability can be exploited over the network without needing physical access. It is difficult for an attacker to exploit this vulnerability and may require special conditions. An attacker does not need any special privileges or access rights. No user interaction is needed for the attacker to exploit this vulnerability. The impact is confined to the system where the vulnerability exists. There is a high impact on the integrity of the data.

Threat Intelligence
5.4

Exploitation attempts have been detected. Elevated vigilance and prompt remediation are advised.

EPSS
4.93%

The exploit probability is very low. The vulnerability is unlikely to be exploited in the next 30 days.

Exploit
Not available

We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.

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