Hi,

The following vulnerability was published for golang-github-lucas-clemente-quic-go.

CVE-2026-40898[0]:
| quic-go is an implementation of the QUIC protocol in Go. Prior to
| version 0.59.1, an attacker can cause excessive memory allocation in
| quic-go's HTTP/3 client and server implementations by sending a
| QPACK-encoded HEADERS frame that decodes into a large trailer field
| section with many unique field names and/or large values. The
| implementation builds an `http.Header` for the corresponding
| `http.Request` or `http.Response`, while only enforcing limits on
| the size of the QPACK-compressed HEADERS frame, not on the decoded
| field section. This can lead to memory exhaustion. This is very
| similar to CVE-2025-64702. The difference is that this issue uses
| HTTP trailers, rather than HTTP headers, as the attack vector. A
| misbehaving or malicious peer can cause a denial-of-service (DoS)
| attack against quic-go's HTTP/3 servers or clients by triggering
| excessive memory allocation, potentially leading to crashes or
| resource exhaustion. This affects both servers and clients due to
| symmetric header construction. Version 0.59.1 enforces RFC 9114
| decoded field section size limits for trailers as well. It
| incrementally decodes QPACK entries and checks the field section
| size after each entry, aborting the stream if an entry causes the
| limit to be exceeded.


If you fix the vulnerability please also make sure to include the
CVE (Common Vulnerabilities & Exposures) id in your changelog entry.

For further information see:

[0] https://security-tracker.debian.org/tracker/CVE-2026-40898
https://www.cve.org/CVERecord?id=CVE-2026-40898
[1] https://github.com/quic-go/quic-go/security/advisories/GHSA-vvgj-x9jq-8cj9

Please adjust the affected versions in the BTS as needed.

Regards,
Salvatore