CVE-2016-4303

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 7.0% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2016-09-26 · updated 2026-06-17
Weakness: CWE-120

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.

Affected products

Debian Linux: 8.0
ES iperf3: from 3.0 before 3.0.12; from 3.1 before 3.1.3 — fixed in 3.0.12, 3.1.3
Novell Suse Package Hub For Suse Linux Enterprise: 12
openSUSE Leap: 42.1
Opensuse: 13.2

How to fix

Upgrade to a fixed version: ES iperf3 3.0.12, 3.1.3. Check the vendor advisory for mitigations.

References

http://blog.talosintel.com/2016/06/esnet-vulnerability.html
http://lists.opensuse.org/opensuse-updates/2016-08/msg00082.html
http://lists.opensuse.org/opensuse-updates/2016-08/msg00090.html
http://software.es.net/iperf/news.html#security-issue-iperf-3-1-3-iperf-3-0-12-released
http://www.talosintelligence.com/reports/TALOS-2016-0164/
https://github.com/esnet/iperf/commit/91f2fa59e8ed80dfbf400add0164ee0e508e412a
https://lists.debian.org/debian-lts-announce/2020/01/msg00023.html
https://raw.githubusercontent.com/esnet/security/master/cve-2016-4303/esnet-secadv-2016-0001.txt.asc
http://blog.talosintel.com/2016/06/esnet-vulnerability.html
http://lists.opensuse.org/opensuse-updates/2016-08/msg00082.html
http://lists.opensuse.org/opensuse-updates/2016-08/msg00090.html
http://software.es.net/iperf/news.html#security-issue-iperf-3-1-3-iperf-3-0-12-released

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