CVE-2021-3466: Buffer Overflow
A flaw was found in libmicrohttpd. A missing bounds check in the postprocessurlencoded function leads to a buffer overflow, allowing a remote attacker to write arbitrary data in an application that uses libmicrohttpd. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability. Only version 0.9.70 is vulnerable.
Other sources
libmicrohttpd 0.9.70 contains a buffer overflow issue in URL parser implemented in the postprocessurlencoded function.
References:
https://git.gnunet.org/libmicrohttpd.git/commit/?id=a110ae6276660bee3caab30e9ff3f12f85cf3241 https://git.gnunet.org/libmicrohttpd.git/diff/src/microhttpd/postprocessor.c?id=a110ae6276660bee3caab30e9ff3f12f85cf3241 https://git.gnunet.org/libmicrohttpd.git/diff/src/microhttpd/testpostprocessor.c?id=a110ae6276660bee3caab30e9ff3f12f85cf3241
— Red Hat
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
redhat/libmicrohttpdto a version that resolves this vulnerability.Fixed in 0.9.71 - Compensating control
If you cannot immediately patch libmicrohttpd, restrict network access to any application that uses libmicrohttpd to trusted clients only to reduce exposure to remote attackers who can exploit the buffer overflow in post_process_urlencoded.
Event History
Frequently Asked Questions
What is the severity of CVE-2021-3466?
CVE-2021-3466 has a high severity rating due to the potential buffer overflow that can compromise data confidentiality.
How do I fix CVE-2021-3466?
To fix CVE-2021-3466, update libmicrohttpd to version 0.9.71 or later.
Which versions of libmicrohttpd are affected by CVE-2021-3466?
CVE-2021-3466 affects libmicrohttpd versions 0.9.70 and earlier.
What types of applications are at risk due to CVE-2021-3466?
Applications that use vulnerable versions of libmicrohttpd are at risk from CVE-2021-3466.
Is CVE-2021-3466 related to any specific operating systems?
Yes, CVE-2021-3466 impacts Red Hat Enterprise Linux and Fedora operating systems running affected versions of libmicrohttpd.