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Fencer Intel
high 7.5

CVE-2026-86259 json

OpenMAIC before 1.0.1 SSRF via Environment-Gated URL Validation

published 2mo ago modified last mo. also EUVD-2026-72126 , GHSA-9m7h-vh2h-rc3w

Unreviewed: the maintainers' own advisory

Published by the maintainers on their GitHub repository THU-MAIC/OpenMAIC. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 36%
public exploits
0
none known

Summary

OpenMAIC before 1.0.1 skips server-side request forgery validation in non-production builds, allowing unauthenticated attackers to reach cloud instance metadata services. Attackers can supply arbitrary provider URLs via the x-base-url header or baseUrl parameter to access sensitive cloud credentials and metadata.

Patch / fix

  • THU-MAIC OpenMAIC 1.0.1

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CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
2mo ago

Exploit prediction

0.42% chance of exploitation in the next 30 days, higher than 36% of all scored CVEs (FIRST EPSS, 2026-11-11).

Exploits and checks

  • github.com https://github.com/THU-MAIC/OpenMAIC/security/advisories/GHSA-9m7h-vh2h-rc3w referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 9.0 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:H/SI:N/SA:N
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:L/A:N
CNA 4.0 9.0 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:H/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

Affected products

  • THU-MAIC OpenMAIC

Classification

Weakness
  • CWE-918 Server-Side Request Forgery
  • CWE-306 Missing Authentication for Critical Functionality

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.

The maintainers of THU-MAIC/OpenMAIC published their own advisory on GitHub. Reviewed sources take precedence over it.