Description
The parse_string function in cjson.c in the cJSON library mishandles UTF8/16 strings, which allows remote attackers to cause a denial of service (crash) or execute arbitrary code via a non-hex character in a JSON string, which triggers a heap-based buffer overflow.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | iperf3 | 3.1.3-1 | — |
| Debian 13 | iperf3 | 3.1.3-1 | — |
| Debian 12 | iperf3 | 3.1.3-1 | — |
| Debian 8 | iperf3 | 3.0.7-1+deb8u1 | DLA-2080-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 16.04 LTS | iperf3 | 3.0.11-1ubuntu0.1~esm1 | USN-4788-1 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SUSE Package Hub 12 | iperf | 3.1.3-6.1 | openSUSE-SU-2016:2121-1, openSUSE-SU-2016:2113-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | iperf | 3.1.3-1.3 | openSUSE-SU-2024:10145-1 |
Advisories 5
- USN-4788-1 iperf3 vulnerability Ubuntu Security Notices (USN) · Jun 25, 2026
- DLA-2080-1 iperf3 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- openSUSE-SU-2024:10145-1 iperf-3.1.3-1.3 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2016:2113-1 Security update for iperf SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2016:2121-1 Security update for iperf SUSE / openSUSE Security Updates · May 7, 2025
References
- http://www.talosintelligence.com/reports/TALOS-2016-0164/
- http://blog.talosintel.com/2016/06/esnet-vulnerability.html
- http://software.es.net/iperf/news.html#security-issue-iperf-3-1-3-iperf-3-0-12-released
- https://raw.githubusercontent.com/esnet/security/master/cve-2016-4303/esnet-secadv-2016-0001.txt.asc
- https://github.com/esnet/iperf/commit/91f2fa59e8ed80dfbf400add0164ee0e508e412a
- openSUSE-SU-2016:2113 vendor-advisory
- openSUSE-SU-2016:2121 vendor-advisory
- [debian-lts-announce] 20200127 [SECURITY] [DLA 2080-1] iperf3 security update mailing-list