Open-Source Security Intelligence

Know every vulnerability
before it knows you.

DevGuard continuously monitors your dependencies and alerts you when CVEs like this one affect your stack — with real-time threat intelligence built for developers.

Search

GHSA-c33x-xqrf-c478

HighCVSS 7.5 / 10
Published Apr 2, 2024·Last modified Feb 4, 2026
Affected Components(0)

No affected components available

Description

An attacker can cause its peer to run out of memory by sending a large number of NEW_CONNECTION_ID frames that retire old connection IDs. The receiver is supposed to respond to each retirement frame with a RETIRE_CONNECTION_ID frame. The attacker can prevent the receiver from sending out (the vast majority of) these RETIRE_CONNECTION_ID frames by collapsing the peers congestion window (by selectively acknowledging received packets) and by manipulating the peer's RTT estimate.

I published a more detailed description of the attack and its mitigation in this blog post: https://seemann.io/posts/2024-03-19-exploiting-quics-connection-id-management/. I also presented this attack in the IETF QUIC working group session at IETF 119: https://youtu.be/JqXtYcZAtIA?si=nJ31QKLBSTRXY35U&t=3683

There's no way to mitigate this attack, please update quic-go to a version that contains the fix.

Risk Scores
Base Score
7.5

The vulnerability can be exploited over the network without needing physical access. It is easy for an attacker to exploit this vulnerability. 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 availability of the system.

Threat Intelligence
6.9

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

EPSS
1.11%

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.

Browse More

Scan your project

Continuously monitor your dependencies and get alerted when vulnerabilities like this one affect your stack.

Checkout DevGuard