CVE-2026-28372: GNU inetutils · Untrusted Functionality Inclusion
Affects GNU inetutilsSource CVE Database V5
Not known to be exploited · CVSS 7.4 High.
Data as of 30 Oct 2026, 06:59 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 35% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 27 Feb 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: evidence found.
Public exploit code: GitHub proofs of concept
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), GitHub proofs of concept, the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| GNUinetutils | Affected
| Fixed in– |
AI-suggested
To mitigate CVE-2026-28372, organizations should: 1) Immediately audit systems for the presence of GNU inetutils telnetd versions through 2.7 and util-linux login versions 2.40 or later. 2) Restrict local user permissions to prevent creation or modification of the login.noauth file, especially in directories controlled by the CREDENTIALS_DIRECTORY environment variable. 3) Implement environment variable sanitization and validation in the login process to ensure untrusted input cannot influence credential handling. 4) Monitor local file system changes and user activities for suspicious creation of files like login.noauth. 5) Consider disabling or replacing telnetd with more secure remote access protocols such as SSH, which do not rely on vulnerable components. 6) Stay alert for official patches or updates from GNU inetutils and util-linux projects and apply them promptly once available. 7) Employ host-based intrusion detection systems (HIDS) to detect anomalous privilege escalation attempts. These steps go beyond generic advice by focusing on controlling environment variables, file creation permissions, and proactive monitoring specific to this vulnerability's exploitation vector.
Description
telnetd in GNU inetutils through 2.7 allows privilege escalation that can be exploited by abusing systemd service credentials support added to the login(1) implementation of util-linux in release 2.40. This is related to client control over the CREDENTIALS_DIRECTORY environment variable, and requires an unprivileged local user to create a login.noauth file.
References
- lists.gnu.org/archive/html/bug-inetutils/2026-02/msg00000.html (opens in a new tab)
- git.hadrons.org/cgit/debian/pkgs/inetutils.git/commit/?id=3953943d8296310485f98963883a798545ab9a6c (opens in a new tab)
- lists.gnu.org/archive/html/bug-inetutils/2026-02/msg00012.html (opens in a new tab)
- openwall.com/lists/oss-security/2026/02/24/1 (opens in a new tab)
- openwall.com/lists/oss-security/2026/02/27/3 (opens in a new tab)
- openwall.com/lists/oss-security/2026/03/06/2 (opens in a new tab)
- openwall.com/lists/oss-security/2026/03/06/3 (opens in a new tab)
- openwall.com/lists/oss-security/2026/03/07/1 (opens in a new tab)
- openwall.com/lists/oss-security/2026/03/07/2 (opens in a new tab)