CVE-2026-24061
Published: January 26, 2026
Official Description
GNU InetUtils contains an argument injection vulnerability in telnetd that could allow for remote authentication bypass via a "-f root" value for the USER environment variable.
CISA KEV Advisory
GNU InetUtils Argument Injection Vulnerability
GNU InetUtils contains an argument injection vulnerability in telnetd that could allow for remote authentication bypass via a "-f root" value for the USER environment variable.
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Risk Analysis
This argument injection vulnerability in GNU InetUtils telnetd allows for remote authentication bypass by manipulating the USER environment variable. With a critical CVSS score of 9.8 and an EPSS score of 0.77919, coupled with its presence in CISA's KEV, this flaw presents an extremely high risk due to its confirmed exploitation and potential for complete system compromise.
This vulnerability is actively being exploited in the wild, confirming its critical nature. It is remotely exploitable by an unauthenticated attacker with low complexity, making it a severe and immediate threat.
Administrators should apply available patches for GNU InetUtils telnetd. Consider disabling telnetd if not strictly necessary, and use more secure protocols like SSH for remote access.
Technical Analysis
CVE-2026-24061 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 9.8.
CISA has added CVE-2026-24061 to the Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. U.S. federal agencies are required to patch this within the mandated timeframe, and all organizations should treat remediation as urgent.
CVSS v3.1 Vector Breakdown
Exploit & PoC Resources
All References (3)
Quick Facts
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-24061 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
- !CISA KEV: Federal agencies must patch per BOD 22-01 timeline
- !Active exploitation confirmed — treat as P1