CVE-2026-27639 json
Mercator vulnerable to stored XSS via unescaped Blade directives in display templates
published 8mo ago modified 4mo ago also EUVD-2026-8613
- cvss
- 5.4
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 25%
- public exploits
- 0
- none known
Summary
Mercator is an open source web application designed to enable mapping of information systems. A stored Cross-Site Scripting (XSS) vulnerability exists in Mercator prior to version 2026.02.22 due to the use of unescaped Blade directives (`{!! !!}`) in display templates. An authenticated user with the User role can inject arbitrary JavaScript payloads into fields such as "contact point" when creating or editing entities. The payload is then executed in the browser of any user who views the affected page, including administrators. Version 2026.02.22 fixes the vulnerability.
Patch / fix
- sourcentis mercator 2026.02.22
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 8mo ago
Exploit prediction
0.33% chance of exploitation in the next 30 days, higher than 25% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.5 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N |
| CNA | 4.0 | 8.5 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/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 |
| NVD | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
Affected products
- dbarzin mercator
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/dbarzin/mercator/commit/839d231399944e43a865198262e96e0218252cc3
patch
-
github.com
/dbarzin/mercator/commit/9902ffd91f287e474729f514c77261f4ef7db8fe
patch
-
github.com
/dbarzin/mercator/commit/c58bb1d2fff18605c61d93cfaf77adca416c560a
patch
-
github.com
/dbarzin/mercator/security/advisories/GHSA-65p7-pph2-966g
mitigation, vendor-advisory
Sources
- CVE List CVE-2026-27639
- NVD CVE-2026-27639
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