LinuxOperating system · Redhat
CVE-1999-1346
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedPAM configuration file for rlogin in Red Hat Linux 6.1 and earlier includes a less restrictive rule before a more restrictive one, which allows users to access the host via rlogin even if rlogin has been explicitly disabled using the /etc/nologin file.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceThe PAM configuration file for rlogin in Red Hat Linux 6.1 and earlier has incorrectly ordered authentication rules, where a permissive rule precedes a restrictive one. This allows users to bypass the /etc/nologin file check and connect via rlogin even when login access should be blocked.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data
LinuxOperating system
<= 6.1CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Authentication
- None
- Confidentiality
- Partial
- Integrity
- Partial
- Availability
- Partial
AV:N/AC:L/Au:N/C:P/I:P/A:P
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify the system versionRun 'cat /etc/redhat-release' or 'uname -a' to determine the Red Hat Linux version. If the system is not Red Hat Linux or is version 6.2 or higher, this CVE does not apply.Affected if The system is Red Hat Linux 6.1 or earlier
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Check if rlogin service is configuredLook for the PAM configuration file for rlogin, typically at /etc/pam.d/rlogin or in /etc/pam.conf. Use 'ls -la /etc/pam.d/rlogin' or 'grep -i rlogin /etc/pam.conf' to locate it.Affected if No PAM configuration file for rlogin exists, meaning rlogin is not in use and the system is not affected
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Examine the PAM auth rule orderOpen the rlogin PAM configuration file and examine the 'auth' section. Look for rules that reference /etc/nologin (such as 'pam_nologin.so' or similar) and identify whether a permissive authentication rule appears BEFORE the nologin check.Affected if A permissive auth rule (that allows authentication without checking nologin) appears before the rule that checks /etc/nologin
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Test the actual behavior with /etc/nologinCreate a temporary /etc/nologin file with a message, then attempt an rlogin connection from another system or local account to verify whether access is incorrectly granted despite the nologin file existing.Affected if Users can successfully rlogin when /etc/nologin exists, bypassing the intended restriction
The system is affected if it is Red Hat Linux 6.1 or earlier, has rlogin configured with PAM, and the PAM configuration shows a permissive auth rule placed before the nologin check rule, allowing connections even when /etc/nologin exists.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataReorder the PAM rules in the rlogin configuration file to place the more restrictive rule (checking for /etc/nologin) before any permissive rules, then verify that rlogin is properly blocked when /etc/nologin exists.
Fix this in Linux
Scoped from the published advisory
- Consultation1.0 h
- Implementation1.0 h
- Testing2.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,376.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-1999-1346 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-1999-1346 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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