Dena H2o
By the Year
In 2023 there have been 2 vulnerabilities in Dena H2o with an average score of 7.9 out of ten. Last year H2o had 1 security vulnerability published. That is, 1 more vulnerability have already been reported in 2023 as compared to last year. However, the average CVE base score of the vulnerabilities in 2023 is greater by 1.95.
| Year | Vulnerabilities | Average Score |
|---|---|---|
| 2023 | 2 | 7.85 |
| 2022 | 1 | 5.90 |
| 2021 | 0 | 0.00 |
| 2020 | 0 | 0.00 |
| 2019 | 0 | 0.00 |
| 2018 | 1 | 9.80 |
It may take a day or so for new H2o vulnerabilities to show up in the stats or in the list of recent security vulnerabilties. Additionally vulnerabilities may be tagged under a different product or component name.
Recent Dena H2o Security Vulnerabilities
The HTTP/2 protocol
CVE-2023-44487
7.5 - High
- October 10, 2023
The HTTP/2 protocol allows a denial of service (server resource consumption) because request cancellation can reset many streams quickly, as exploited in the wild in August through October 2023.
Resource Exhaustion
H2O is an HTTP server
CVE-2023-30847
8.2 - High
- April 27, 2023
H2O is an HTTP server. In versions 2.3.0-beta2 and prior, when the reverse proxy handler tries to processes a certain type of invalid HTTP request, it tries to build an upstream URL by reading from uninitialized pointer. This behavior can lead to crashes or leak of information to back end HTTP servers. Pull request number 3229 fixes the issue. The pull request has been merged to the `master` branch in commit f010336. Users should upgrade to commit f010336 or later.
Access of Uninitialized Pointer
h2o is an open source http server
CVE-2021-43848
5.9 - Medium
- February 01, 2022
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.
Use of Uninitialized Resource
Buffer overflow in H2O version 2.2.4 and earlier
CVE-2018-0608
9.8 - Critical
- June 26, 2018
Buffer overflow in H2O version 2.2.4 and earlier allows remote attackers to execute arbitrary code or cause a denial of service (DoS) via unspecified vectors.
Buffer Overflow
Buffer overflow in H2O version 2.2.2 and earlier
CVE-2017-10869
7.5 - High
- December 22, 2017
Buffer overflow in H2O version 2.2.2 and earlier allows remote attackers to cause a denial-of-service in the server via unspecified vectors.
Buffer Overflow
H2O version 2.2.3 and earlier
CVE-2017-10872
6.5 - Medium
- December 22, 2017
H2O version 2.2.3 and earlier allows remote attackers to cause a denial of service in the server via unspecified vectors.
Range Error
H2O version 2.2.3 and earlier
CVE-2017-10908
7.5 - High
- December 22, 2017
H2O version 2.2.3 and earlier allows remote attackers to cause a denial of service in the server via specially crafted HTTP/2 header.
Improper Input Validation
H2O version 2.2.2 and earlier
CVE-2017-10868
7.5 - High
- December 22, 2017
H2O version 2.2.2 and earlier allows remote attackers to cause a denial of service in the server via specially crafted HTTP/1 header.
Improper Input Validation
Use-after-free vulnerability in H2O
CVE-2016-7835
9.1 - Critical
- June 09, 2017
Use-after-free vulnerability in H2O allows remote attackers to cause a denial-of-service (DoS) or obtain server certificate private keys and possibly other information.
Dangling pointer
lib/http2/connection.c in H2O before 1.7.3 and 2.x before 2.0.0-beta5 mishandles HTTP/2 disconnection, which
CVE-2016-4817
7.5 - High
- June 19, 2016
lib/http2/connection.c in H2O before 1.7.3 and 2.x before 2.0.0-beta5 mishandles HTTP/2 disconnection, which allows remote attackers to cause a denial of service (use-after-free and application crash) or possibly execute arbitrary code via a crafted packet.<a href="http://cwe.mitre.org/data/definitions/416.html">CWE-416: Use After Free</a>
CRLF injection vulnerability in the on_req function in lib/handler/redirect.c in H2O before 1.6.2 and 1.7.x before 1.7.0-beta3
CVE-2016-1133
3.7 - Low
- January 16, 2016
CRLF injection vulnerability in the on_req function in lib/handler/redirect.c in H2O before 1.6.2 and 1.7.x before 1.7.0-beta3 allows remote attackers to inject arbitrary HTTP headers and conduct HTTP response splitting attacks via a crafted URI.<a href="https://cwe.mitre.org/data/definitions/93.html">CWE-93: Improper Neutralization of CRLF Sequences ('CRLF Injection')</a>
