Buffer overflow in GNU Libmicrohttpd
CVE-2021-3466
A flaw was found in libmicrohttpd. A missing bounds check in the post_process_urlencoded 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.
Vulnerability class: Buffer Overflow
EPSS: 0.087 (94.6th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Gnu Libmicrohttpd — versions 0.9.70
- Fedoraproject Fedora — versions 32, 33, 34
- Redhat Enterprise_linux — versions 6.0, 7.0, 8.0
- N/a Libmicrohttpd — versions libmicrohttpd 0.9.70
Weakness classification (CWE)
Public proof-of-concept exploits
References
- secalert@redhat.com (Patch, Third Party Advisory, Issue Tracking)
- secalert@redhat.com (vendor-advisory)
- secalert@redhat.com (vendor-advisory)
- secalert@redhat.com (vendor-advisory)
- secalert@redhat.com (vendor-advisory)
Frequently asked questions
- What is CVE-2021-3466?
- CVE-2021-3466 is a critical-severity vulnerability in GNU Libmicrohttpd, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2021-03-25.
- How severe is CVE-2021-3466?
- Critical severity. CVSS v3 base score is 9.8 out of 10.
- Is CVE-2021-3466 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.