CVE-2021-43848
Summary
| CVE | CVE-2021-43848 |
|---|---|
| State | PUBLIC |
| Assigner | [email protected] |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2022-02-01 13:15:00 UTC |
| Updated | 2022-02-07 21:11:00 UTC |
| Description | h2o is an open source http server. In code prior to the `8c0eca3` commit h2o may attempt to access uninitialized memory. When receiving QUIC frames in certain order, HTTP/3 server-side implementation of h2o can be misguided to treat uninitialized memory as HTTP/3 frames that have been received. When h2o is used as a reverse proxy, an attacker can abuse this vulnerability to send internal state of h2o to backend servers controlled by the attacker or third party. Also, if there is an HTTP endpoint that reflects the traffic sent from the client, an attacker can use that reflector to obtain internal state of h2o. This internal state includes traffic of other connections in unencrypted form and TLS session tickets. This vulnerability exists in h2o server with HTTP/3 support, between commit 93af138 and d1f0f65. None of the released versions of h2o are affected by this vulnerability. There are no known workarounds. Users of unreleased versions of h2o using HTTP/3 are advised to upgrade immediately. |
Risk And Classification
Problem Types: CWE-908
NVD Known Affected Configurations (CPE 2.3)
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| postpone stream shutdown by H3 frame parsers · h2o/h2o@8c0eca3 · GitHub | MISC | github.com | |
| Unititialized memory access in HTTP/3 server-side implementation · Advisory · h2o/h2o · GitHub | CONFIRM | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
Legacy QID Mappings
- 690783 Free Berkeley Software Distribution (FreeBSD) Security Update for h2o (1d3677a8-9143-42d8-84a3-0585644dff4b)