Quick answers
- Is CVE-2026-6328 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-6328 being exploited in the wild.
- How severe is CVE-2026-6328?
- Informational severity, with a CVSS score of 8.3, published 15 April 2026.
- Which products and versions are affected?
- Alibaba Xquic through 1.8.3.
- Is there a fix for CVE-2026-6328?
- A patch was published on 2026-04-15: Fix committed to GitHub repository Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-6328 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-6328?
- Check whether you run Alibaba Xquic at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A vulnerability exists in XQUIC's packet processing module, specifically within the STREAM frame handler. The implementation fails to properly validate the presence of STREAM frames in Initial (INIT) and Handshake (HSK) packets, which are prohibited by the QUIC specification. An unauthenticated remote attacker can exploit this by sending malformed packets to trigger improper protocol states or bypass cryptographic signature verification steps. The fix involves explicitly checking the packet type in `xqc_process_stream_frame` and closing connections that include illegal STREAM frames with a PROTOCOL_VIOLATION error.
Affected products
- Alibaba xquic through 1.8.3
Timeline
- 2026-04-15: advisory: CVE published by Alibaba, Inc.
- 2026-04-15: patched: Fix committed to GitHub repository