CVE-2000-0166: Buffer overflow in the InterAccess telnet server TelnetD allows remote attackers to execute commands via a lon

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HIGH 10.0DOWNGRADE

CVE-2000-0166 is a high-severity flaw (CVSS 10.0) affecting interaccess telnetd server. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Buffer overflow in the InterAccess telnet server TelnetD allows remote attackers to execute commands via a long login name.

Why this priority

Critical severity
EPSS top 7%: very likely to be exploited
Public exploit reference

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	10.0 (High)
EPSS exploit chance	5.8% (top 7%)
CISA exploited list	No
Published	2000-02-21
Last modified	2026-06-16

Publisher (CNA): MITRE · Vendor: interaccess

Last updated 2026-06-16 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2000-02-21 05:00 UTCPublished CVE record published
2026-06-16 21:51 UTCUpdated Record last modified

interaccess interaccess telnetd server DOWNGRADE

Affected: 4.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 4.0

1. Check installed version

apt-cache policy interaccess-telnetd-server || rpm -q interaccess-telnetd-server || interaccess-telnetd-server --version

2. No fixed release: DOWNGRADE to a release before 4.0 (Debian / Ubuntu)

apt-cache madison interaccess-telnetd-server sudo apt install interaccess-telnetd-server=<VERSION_BEFORE_4.0> sudo apt-mark hold interaccess-telnetd-server

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list interaccess-telnetd-server sudo dnf downgrade interaccess-telnetd-server-<VERSION_BEFORE_4.0> sudo dnf versionlock add interaccess-telnetd-server

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Public exploits and detection

Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.

Exploit-DB: Pragma Systems InterAccess TelnetD Server 4.0 Build 4 - Buffer Overflow

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2000-0166?

interaccess telnetd server: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2000-0166 being exploited?

CVE-2000-0166 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2000-0166 affect?

CVE-2000-0166 affects interaccess telnetd server. Severity is high (CVSS 10.0). Buffer overflow in the InterAccess telnet server TelnetD allows remote attackers to execute commands via a long login name.

How urgent is CVE-2000-0166?

Priority 63/100. Critical severity; EPSS top 7%: very likely to be exploited; Public exploit reference

Related CVEs

CVE-2000-0212 MEDIUM 5.0 DOWNGRADE InterAccess TelnetD Server 4.0 allows remote attackers to conduct a denial of service via malformed terminal c

References

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