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Fencer Intel
high 7.2

CVE-2026-27177 json

MajorDoMo Stored Cross-Site Scripting via Property Set Endpoint

published 8mo ago modified yesterday also EUVD-2026-8389

cvss
7.2
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 13%
public exploits
0
none known

Summary

MajorDoMo (aka Major Domestic Module) contains a stored cross-site scripting (XSS) vulnerability via the /objects/?op=set endpoint, which is intentionally unauthenticated for IoT device integration. User-supplied property values are stored raw in the database without sanitization. When an administrator views the property editor in the admin panel, the stored values are rendered without escaping in both a paragraph tag (SOURCE field) and a textarea element (VALUE field). The XSS fires on page load without requiring any click from the admin. Additionally, the session cookie lacks the HttpOnly flag, enabling session hijack via document.cookie exfiltration. An attacker can enumerate properties via the unauthenticated /api.php/data/ endpoint and poison any property with malicious JavaScript.

Patch / fix

Is CVE-2026-27177 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
8mo ago

Exploit prediction

0.23% chance of exploitation in the next 30 days, higher than 13% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • github.com https://github.com/sergejey/majordomo/pull/1177 referenced PoC, tagged "exploit" by a source, unverified
  • chocapikk.com https://chocapikk.com/posts/2026/majordomo-revisited/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 5.3 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N
CNA 3.1 7.2 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
CNA 4.0 5.3 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/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
NVD 3.1 6.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Affected products

  • sergejey MajorDoMo

Classification

Weakness
  • CWE-79 Improper Neutralization of Input During Web Page Generation

References

Sources

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.