CVE-2021-43848

Source
https://nvd.nist.gov/vuln/detail/CVE-2021-43848
Import Source
https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2021-43848.json
JSON Data
https://api.test.osv.dev/v1/vulns/CVE-2021-43848
Related
Published
2022-02-01T13:15:09Z
Modified
2025-01-08T13:46:10.186149Z
Severity
  • 5.9 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N CVSS Calculator
Summary
[none]
Details

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.

References

Affected packages

Git / github.com/h2o/h2o

Affected ranges

Type
GIT
Repo
https://github.com/h2o/h2o
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
Fixed

Affected versions

v0.*

v0.9.0
v0.9.1
v0.9.2

v1.*

v1.0.0
v1.0.1
v1.1.0
v1.1.1
v1.2.0
v1.3.0
v1.3.0-beta1
v1.3.1
v1.4.0
v1.4.1
v1.4.2
v1.5.0
v1.5.0-beta1
v1.5.0-beta2
v1.5.0-beta3
v1.5.0-beta4
v1.5.1
v1.5.2
v1.5.3
v1.6.0
v1.6.0-beta1
v1.6.0-beta2
v1.7.0
v1.7.0-beta1
v1.7.0-beta2
v1.7.0-beta3
v1.7.0-beta4
v1.7.0-beta5

v2.*

v2.1.0-beta1
v2.1.0-beta2
v2.1.0-beta3
v2.2.0
v2.2.0-beta1
v2.2.0-beta2
v2.2.0-beta3