CVE-2020-4126
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 · uneditedHCL iNotes is susceptible to a sensitive cookie exposure vulnerability. This can allow an unauthenticated remote attacker to capture the cookie by intercepting its transmission within an http session. Fixes are available in HCL Domino and iNotes versions 10.0.1 FP6 and 11.0.1 FP2 and later.
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 confidenceHCL iNotes fails to properly secure sensitive cookies during HTTP transmission, allowing an unauthenticated remote attacker to intercept and capture session cookies by monitoring network traffic. This cookie exposure occurs when cookies are transmitted over unencrypted HTTP sessions rather than being restricted to HTTPS connections.
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>= 9.0, < 10.0.1>= 11.0.0, < 11.0.1= 10.0.1= 11.0.1CVSS 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
- High
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
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 installed iNotes versionLocate the HCL iNotes installation and retrieve its version number (typically via Domino server console, notes.ini, or iNotes web UI footer). Compare the installed version against the affected ranges: 9.0 through 10.0.1 (excluding 10.0.1 FP6+), 11.0.0 through 11.0.1 (excluding 11.0.1 FP2+).Affected if The installed version falls within 9.0 to <10.0.1, 10.0.1, 11.0.0 to <11.0.1, or 11.0.1 (without later FP updates).
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Verify cookie Secure flag configurationExamine the Domino server configuration and iNotes settings for cookie security. Check if cookies (particularly session cookies) are configured with the Secure attribute. This may be in the Domino Directory, notes.ini, or iNotes configuration documents.Affected if Cookies are missing the Secure flag or the configuration does not enforce Secure=True for session cookies.
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Confirm HTTP (non-HTTPS) access is enabledCheck whether the Domino server and iNotes allow HTTP connections (port 80) in addition to HTTPS (port 443). Review the server's HTTP task configuration and listener ports.Affected if HTTP access on port 80 or non-SSL ports is enabled and accessible for iNotes.
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Inspect cookie transmission over networkCapture and inspect network traffic between a client and the iNotes server during authentication and session establishment. Verify whether cookies are transmitted over unencrypted HTTP connections.Affected if Session cookies are observed being transmitted over plain HTTP rather than exclusively over HTTPS.
A user is affected if their iNotes version is within the listed vulnerable ranges AND cookies are transmitted over HTTP rather than being restricted to HTTPS with the Secure flag set.
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 data10.0.111.0.1
Apply HCL Domino and iNotes version 10.0.1 FP6 or 11.0.1 FP2 or later to patch the vulnerability. Additionally, ensure cookies are configured with the Secure flag and transmitted only over HTTPS to prevent interception.
- Consultation2.0 h
- Implementation4.0 h
- Testing2.0 h
- Review / QA1.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2020-4126 — 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-2020-4126 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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- Version or environment caveats, and links to real fixes
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