Vulnerability Analysis
keeper.sh Calendar version prior to 2.18.14 SSRF Guard Bypass via DNS Rebinding
CVE-2026-75583
keeper.sh's calendar module version prior to 2.18.14 contains a server-side request forgery (SSRF) guard bypass vulnerability that allows authenticated attackers to reach private network addresses by exploiting a DNS rebinding attack against the two-phase URL validation and connection flow. The SSRF guard validates a hostname's resolved IP addresses but discards them before the actual HTTP connection is opened, allowing an attacker who controls authoritative DNS to return a public address during validation and a private address during the subsequent independent socket-level DNS resolution, causing the guard to pass while the outbound connection reaches internal infrastructure such as cloud instance metadata endpoints.
No Active Exploit Signals
CVSS Base Score
2.3
LOW
Exploitability:-
Impact Score:-
Temporal Score:-
EPSS:-
Threat Intelligence Signals
CISA KEV
No
KEV Date Added
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Ransomware Use
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KEV Due Date
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VulnCheck In-the-Wild
No
Nuclei Template
No
EPSS Score
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EPSS Percentile
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GHSA ID
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GitHub Severity
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SSVC Exploitation
None
SSVC Automatable
No
Vulnerability Class
—
Identity & Timeline
| Status | - |
| Assigning Authority | - |
| CVSS Version / Source | - |
| Reserved | - |
| Published | - |
| Patch Date (date_public) | - |
| Exploit DB Date | - |
| First GitHub PoC Date | - |
| Last Updated | - |
| Time to Patch (Days to fix) | - |
| Exploit Release Gap | - |
| PoC Release Gap | - |
| Exploit DB References | None identified |
Affected Products & Versions
| Vendor | Product | Affected Versions |
|---|---|---|
| No affected products specified. | ||
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