What’s Vulnerable › Vulnerabilities
CVE-2020-10188
- Severity: critical (CVSS 9.8 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 74.3% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2020-03-06 · updated 2026-06-17
- Weakness: CWE-120
Description
utility.c in telnetd in netkit telnet through 0.17 allows remote attackers to execute arbitrary code via short writes or urgent data, because of a buffer overflow involving the netclear and nextitem functions.
Affected products
- Arista Networks EOS: through 4.20.15; from 4.21.0 through 4.21.10m; from 4.22 through 4.22.4m; from 4.23 through 4.23.3m; 4.24.0f
- Debian Linux: 8.0, 9.0
- Fedoraproject Fedora: 30, 31, 32
- Juniper Junos OS: 12.3, 12.3-r1, 12.3-r10, 12.3-r10-s1, 12.3-r10-s2, 12.3-r11 (+335)
- Netkit Telnet Project Netkit Telnet: through 0.17
- Oracle Communications Performance Intelligence Center: 10.4.0.2
References
- https://appgateresearch.blogspot.com/2020/02/bravestarr-fedora-31-netkit-telnetd_28.html
- https://github.com/krb5/krb5-appl/blob/d00cd671dfe945791b33d4f1f6a5c57ae1667ef8/telnet/telnetd/utility.c#L205-L216
- https://lists.debian.org/debian-lts-announce/2020/05/msg00012.html
- https://lists.debian.org/debian-lts-announce/2020/08/msg00038.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7FMTRRQTYKWZD2GMXX3GLZV46OLPCLVK/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HLU6FL24BSQQEB2SJC26NLJ2MANQDA7M/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/K3VJ6V2Z3JRNJOBVHSOPMAC76PSSKG6A/
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-telnetd-EFJrEzPx
- https://www.arista.com/en/support/advisories-notices/security-advisories/10702-security-advisory-48
- https://www.oracle.com/security-alerts/cpuApr2021.html
- http://www.openwall.com/lists/oss-security/2026/01/20/8
- https://appgateresearch.blogspot.com/2020/02/bravestarr-fedora-31-netkit-telnetd_28.html
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