CVE-2026-27639

MEDIUMNVD 5.45.4—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.4 under NVD CVSS v3. EPSS exploit probability: 0.3%, top 80% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
5.4EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.4Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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.

CVSS v3
5.4
EG Score
5.4(medium)
EG Risk
29(Track)
EG Risk 29/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity54% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
21%
KEV
Not listed

Published

February 25, 2026

Last Modified

June 17, 2026

Advisory Details (4)

Auto-updated Aug 4, 2026
🔬 Proof of concept available. Patch available. Sources: github, github_commit.
github Patch Available🟡 PoC Available

Stored XSS via unescaped Blade directives in display templates · Advisory · sourcentis/mercator · GitHub

https://github.com/dbarzin/mercator/security/advisories/GHSA-65p7-pph2-966g
github_commit Patch Available

commit c58bb1d2fff1 (dbarzin/mercator)

Patch available: dbarzin/mercator 2026.02.24 (contains commit c58bb1d2fff1)

https://github.com/dbarzin/mercator/commit/c58bb1d2fff18605c61d93cfaf77adca416c560a
github_commit Patch Available

commit 9902ffd91f28 (dbarzin/mercator)

Patch available: dbarzin/mercator 2026.02.24 (contains commit 9902ffd91f28)

https://github.com/dbarzin/mercator/commit/9902ffd91f287e474729f514c77261f4ef7db8fe
github_commit Patch Available

commit 839d23139994 (dbarzin/mercator)

Patch available: dbarzin/mercator 2026.02.24 (contains commit 839d23139994)

https://github.com/dbarzin/mercator/commit/839d231399944e43a865198262e96e0218252cc3

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 8× in last 7d / 27× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-09-20 20:15 UTCEPSS rescore
  2. 2026-09-20 20:15 UTCEPSS rescore
  3. 2026-09-18 19:28 UTCEPSS rescore
  4. 2026-09-18 19:27 UTCEPSS rescore
  5. 2026-09-18 19:20 UTCOSV refresh
  6. 2026-09-17 19:30 UTCEPSS rescore
  7. 2026-09-16 14:08 UTCEPSS rescore
  8. 2026-09-16 05:15 UTCEPSS rescore
  9. 2026-09-13 16:47 UTCEPSS rescore
  10. 2026-09-12 15:01 UTCEPSS rescore
  11. 2026-09-11 14:52 UTCEPSS rescore
  12. 2026-09-10 09:34 UTCEPSS rescore
  13. 2026-09-08 22:00 UTCEPSS rescore
  14. 2026-09-07 16:01 UTCEPSS rescore
  15. 2026-09-06 13:47 UTCEPSS rescore
  16. 2026-09-06 13:47 UTCEPSS rescore
  17. 2026-09-04 05:06 UTCEPSS rescore
  18. 2026-09-02 14:11 UTCEPSS rescore
  19. 2026-09-01 13:53 UTCEPSS rescore
  20. 2026-09-01 04:39 UTCEPSS rescore
  21. 2026-08-30 22:47 UTCOSV refresh
  22. 2026-08-30 19:17 UTCEPSS rescore
  23. 2026-08-30 01:22 UTCEPSS rescore
  24. 2026-08-28 21:41 UTCEPSS rescore
  25. 2026-08-27 14:25 UTCEPSS rescore
Show 36 more
  1. 2026-08-26 14:46 UTCEPSS rescore
  2. 2026-08-25 13:48 UTCEPSS rescore
  3. 2026-08-23 00:19 UTCEPSS rescore
  4. 2026-08-21 23:49 UTCEPSS rescore
  5. 2026-08-20 22:55 UTCEPSS rescore
  6. 2026-08-19 17:03 UTCEPSS rescore
  7. 2026-08-18 13:48 UTCEPSS rescore
  8. 2026-08-17 13:47 UTCEPSS rescore
  9. 2026-08-16 14:56 UTCEPSS rescore
  10. 2026-08-16 02:14 UTCEPSS rescore
  11. 2026-08-15 01:30 UTCEPSS rescore
  12. 2026-08-14 09:03 UTCEG score recompute
  13. 2026-08-13 22:00 UTCEPSS rescore
  14. 2026-08-13 02:06 UTCEG score recompute
  15. 2026-08-12 13:50 UTCEPSS rescore
  16. 2026-08-12 00:48 UTCEG score recompute
  17. 2026-08-11 13:42 UTCEPSS rescore
  18. 2026-08-11 00:00 UTCEPSS rescore
  19. 2026-08-10 09:59 UTCEG score recompute
  20. 2026-08-09 13:46 UTCEPSS rescore
  21. 2026-08-09 08:41 UTCEG score recompute
  22. 2026-08-08 16:37 UTCEPSS rescore
  23. 2026-08-07 20:45 UTCEG score recompute
  24. 2026-08-06 13:46 UTCEPSS rescore
  25. 2026-08-06 03:03 UTCEG score recompute
  26. 2026-08-05 19:17 UTCEPSS rescore
  27. 2026-08-04 15:10 UTCEPSS rescore
  28. 2026-08-04 05:55 UTCEG score recompute
  29. 2026-08-03 10:36 UTCEPSS rescore
  30. 2026-08-02 19:36 UTCEG score recompute
  31. 2026-08-02 02:26 UTCEPSS rescore
  32. 2026-08-01 04:16 UTCEPSS rescore
  33. 2026-07-30 16:27 UTCEPSS rescore
  34. 2026-07-30 01:30 UTCEPSS rescore
  35. 2026-07-28 15:36 UTCEPSS rescore
  36. 2026-07-27 14:07 UTCEG score recompute

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-27639?
CVE-2026-27639 is a medium vulnerability published on February 25, 2026. 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…
When was CVE-2026-27639 disclosed?
CVE-2026-27639 was first published in the National Vulnerability Database on February 25, 2026, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-27639 actively exploited?
CVE-2026-27639 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 79.4% of all scored CVEs.
What is the CVSS score of CVE-2026-27639?
CVE-2026-27639 has a CVSS v3 base score of 5.4 (NVD).
How do I remediate CVE-2026-27639?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-27639, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-27639

Explore →

Is Your Infrastructure Affected by CVE-2026-27639?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs