CVE-2020-10188
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.
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 74.3%, higher than 99% of all known CVEs. Patch or mitigate before the next change window.
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.
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 74.34% probability · 99th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-120
- Affected
- netkit telnet project/netkit telnet · fedoraproject/fedora · debian/debian linux · arista/eos · oracle/communications performance intelligence center · juniper/junos
- Source
- cve@mitre.org
EPSS 74.3% since 26 October 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://appgateresearch.blogspot.com/2020/02/bravestarr-fedora-31-netkit-telnetd_28.htmlThird Party Advisory
- https://github.com/krb5/krb5-appl/blob/d00cd671dfe945791b33d4f1f6a5c57ae1667ef8/telnet/telnetd/utility.c#L205-L216Patch, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2020/05/msg00012.htmlMailing List, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2020/08/msg00038.htmlMailing List, Third Party Advisory
- 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-EFJrEzPxThird Party Advisory
- https://www.arista.com/en/support/advisories-notices/security-advisories/10702-security-advisory-48Third Party Advisory
- https://www.oracle.com/security-alerts/cpuApr2021.htmlPatch, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2026/01/20/8
- https://appgateresearch.blogspot.com/2020/02/bravestarr-fedora-31-netkit-telnetd_28.htmlThird Party Advisory
- https://github.com/krb5/krb5-appl/blob/d00cd671dfe945791b33d4f1f6a5c57ae1667ef8/telnet/telnetd/utility.c#L205-L216Patch, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2020/05/msg00012.htmlMailing List, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2020/08/msg00038.htmlMailing List, Third Party Advisory
- 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-EFJrEzPxThird Party Advisory
- https://www.arista.com/en/support/advisories-notices/security-advisories/10702-security-advisory-48Third Party Advisory
- https://www.oracle.com/security-alerts/cpuApr2021.htmlPatch, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.