CVE-2025-29785 quic-go Has Panic in Path Probe Loss Recovery Handling
A malicious QUIC client can trigger a nil-pointer dereference in quic-go, causing a denial of service via crafted path probe acknowledgments.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-29785?
CVE-2025-29785 is a high-severity vulnerability in quic-go, published on 2 Jun 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
quic-go is an implementation of the QUIC protocol in Go. The loss recovery logic for path probe packets that was added in the v0.50.0 release can be used to trigger a nil-pointer dereference by a malicious QUIC client. In order to do so, the attacker first sends valid QUIC packets from different remote addresses (thereby triggering the newly added path validation logic: the server sends path probe packets), and then sending ACKs for packets received from the server specifically crafted to trigger the nil-pointer dereference. v0.50.1 contains a patch that fixes the vulnerability. This release contains a test that generates random sequences of sent packets (both regular and path probe packets), that was used to verify that the patch actually covers all corner cases. No known workarounds are available.
Weakness: CWE-248
Which versions are affected by CVE-2025-29785?
3 open source packages ship an affected version, including github.com/quic-go/quic-go.
| Package | Affected | Fixed in |
|---|---|---|
github.com/quic-go/quic-go Go | From 0.50.0 | 0.50.1 |
github.com/quic-go/quic-go Go | From 0.50.0 | 0.50.1 |
github.com/quic-go/quic-go Go | From 0.50.0 | 0.50.1 |
How do I fix CVE-2025-29785?
Upgrade github.com/quic-go/quic-go to 0.50.1 or later.
Is CVE-2025-29785 being exploited?
There is no known exploitation of CVE-2025-29785 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2025-29785, GHSA-j972-j939-p2v3, GO-2025-3735, UBUNTU-CVE-2025-29785.