Multiple integer overflows in the evbuffer API in Libevent 1.4.x before 1.4.15, 2.0.x before 2.0.22, and 2.1.x before 2.1.5-beta allow context-dependent attackers to cause a denial of service or possibly have other unspecified impact via "insanely large inputs" to the (1) evbuffer_add, (2) evbuffer_expand, or (3) bufferevent_write function, which triggers a heap-based buffer overflow or an infinite loop. NOTE: this identifier has been SPLIT per ADT3 due to different affected versions. See CVE-2015-6525 for the functions that are only affected in 2.0 and later.
CVSS Details
- CVSS 3.1 Base Score: 9.8
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Amazon Linux Ami 2 | — | Upgrade libevent-debuginfoUpgrade libeventUpgrade libevent-develUpgrade libevent-doc | Apr 27, 2020 | Aug 24, 2015 |
| Debian | — | Upgrade libevent | Jul 30, 2024 | Aug 24, 2015 |
| Freebsd | — | Upgrade libevent2Upgrade libevent | Dec 10, 2025 | Jan 11, 2015 |
| Gentoo Linux | — | Upgrade dev-libs/libevent. | Oct 30, 2017 | Aug 24, 2015 |
| Huawei Euleros 2_0_sp2 | — | Upgrade libevent | Dec 4, 2019 | Aug 24, 2015 |
| Huawei Euleros 2_0_sp3 | — | Upgrade libevent | Jun 28, 2018 | Aug 24, 2015 |
| Oracle Solaris | — | Upgrade entire/ to version 11.4-11.4.0.0.1.15.0 on Solaris 11.4 | Oct 19, 2018 | Aug 24, 2015 |
| Redhat_linux | — | No solution exists | Jul 9, 2025 | Jan 5, 2015 |
| Suse | — | Upgrade libevent-1_4-2Upgrade libevent-2_0-5Upgrade libevent-develUpgrade libevent-2_1-8 | Dec 18, 2015 | Oct 10, 2014 |
| Ubuntu | — | Upgrade libevent-2.0-5Upgrade libevent-1.4-2 | Nov 8, 2024 | Aug 24, 2015 |
Prioritise with Active Threat Intelligence
With curated Threat Intelligence, you can see which vulnerabilities truly put you at risk, prioritize what matters most, and act before attackers do.
Explore Intelligence Hub