CVE-2020-10188
What it is
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.
At a glance
- Exploitability
- Can be exploited over the network without logging in. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 74.3% chance of exploitation in the next 30 days (EPSS). Higher than most.
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- ReservedThe CVE id was reserved by its CNA
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 74.3% in the next 30 days (EPSS).
- Severity: 9.8 CRITICAL (CVSS).
- Fix: a patch or advisory is linked.
- It meets the bar for Drop everything: critical, and exploited or very likely to be.
Details
- Published
- Last modified
- Exploit probability
- 74.3% · EPSS, next 30 days
- Weakness
- CWE-120 · Classic buffer overflow
- Record status
- Modified
Affected
- Netkit Telnet Project Netkit Telnet ≤ 0.17
- Fedoraproject Fedora 30
- Fedoraproject Fedora 31
- Fedoraproject Fedora 32
- Debian Linux 8.0
- Debian Linux 9.0
- Arista Eos ≤ 4.20.15
- Arista Eos ≤ 4.21.10m
Attack profile CVSS 3.1 · 9.8
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2020-10188.md and follow it. Check whether this project is affected by CVE-2020-10188. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://github.com/krb5/krb5-appl/blob/d00cd671dfe945791b33d4f1f6a5c57ae1667ef8/telnet/telnetd/utility.c#L205-L216
- https://www.oracle.com/security-alerts/cpuApr2021.html
- https://github.com/krb5/krb5-appl/blob/d00cd671dfe945791b33d4f1f6a5c57ae1667ef8/telnet/telnetd/utility.c#L205-L216
- https://www.oracle.com/security-alerts/cpuApr2021.html
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
- 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