CVE-2026-100523 json
Cotonti through 1.0.0 Open Redirect via message.php redirect parameter
published last mo. modified last mo. also EUVD-2026-87378
- cvss
- 6.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 8%
- public exploits
- 0
- none known
Summary
Cotonti through 1.0.0 contains an open redirect vulnerability in message.php that base64-decodes the redirect parameter without domain validation. Unauthenticated attackers can craft malicious links with encoded external URLs to redirect users to arbitrary sites via meta refresh tags for phishing attacks.
Patch / fix
- github.com/Cotonti/Cotonti#1908 pull request
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- last mo.
Exploit prediction
0.19% chance of exploitation in the next 30 days, higher than 8% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 5.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N |
| CNA | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| CNA | 4.0 | 5.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- Cotonti Cotonti
Classification
- Weakness
-
- CWE-601 URL Redirection to Untrusted Site
References
-
github.com
/Cotonti/Cotonti/pull/1908
issue-tracking, patch
-
github.com
/Cotonti/Cotonti/issues/1907
issue-tracking
-
github.com
/Cotonti/Cotonti/blob/1.0.0/message.php
technical-description
-
github.com
/Cotonti/Cotonti/blob/1.0.0/system/common.php
technical-description
-
github.com
/Cotonti/Cotonti
product
-
vulncheck.com
/advisories/cotonti-through-1.0.0-open-redirect-via-message-php-redirect-parameter
third-party-advisory
Sources
- CVE List CVE-2026-100523
- NVD CVE-2026-100523
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.