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NVD / CVE Program· CNA GitHub_M

CVE-2025-27509: SAML authentication vulnerability due to improper SAML response validation

CriticalCVSS 9.3 · v4.0—Proof of concept Fix available

Noroxi assessment

Priority: Monitor (action score 37/100)

  • Public proof-of-concept code exists (GitHub); there is no record of exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.66% (FIRST EPSS); higher than 52.3% of all records.
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • According to CISA the attack is automatable: targets can be found by mass scanning.
  • Fixed version: fleetdm fleet 4.64.2.

Low priority for now. Upgrade to fleetdm fleet 4.64.2 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

fleetdm/fleet is an open source device management, built on osquery. In vulnerable versions of Fleet, an attacker could craft a specially-formed SAML response to forge authentication assertions, provision a new administrative user account if Just-In-Time (JIT) provisioning is enabled, or create new accounts tied to forged assertions if f MDM enrollment is enabled. This vulnerability is fixed in 4.64.2, 4.63.2, 4.62.4, and 4.58.1.

Published
Mar 6, 2025
Updated
Jun 17, 2026
EPSS
0.6% · 52th percentile

Report tools

JSON

Action score

37

Monitor

Low priority for now.

CVSS
37 / 40 · 9.3 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.6%

CISA SSVC decision

Exploitation
none
Automatable
yes
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · GitHub_M
9.3
NVD has not scored this yet; the score shown is the CNA’s.

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • Proof of concept exists, no weaponized module
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2025-27509

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

—

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

  • fleetdm fleet

    • >= 4.64.0, < 4.64.2, >= 4.63.0, < 4.63.2, >= 4.62.0, < 4.62.4, < 4.58.1affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Gogithub.com/fleetdm/fleet/v4from 0—
Gogithub.com/fleetdm/fleet/v4from 4.54.0 · before 4.58.14.58.1
Gogithub.com/fleetdm/fleet/v4from 4.62.0 · before 4.62.44.62.4
Gogithub.com/fleetdm/fleet/v4from 4.63.0 · before 4.63.24.63.2
Gogithub.com/fleetdm/fleet/v4from 4.64.0 · before 4.64.24.64.2
Gogithub.com/fleetdm/fleet/v4before 4.53.24.53.2

Same product

fleetdm: all records

Other highest-scoring records for the same primary product.

  • CVE-2020-26276SAML authentication vulnerability in Fleet
    40Plan
  • CVE-2026-103264Fleet before 4.87.0 Authentication Bypass via Device Identifiers
    37Monitor
  • CVE-2026-23518Fleet has a JWT signature bypass vulnerability in Azure AD MDM enrollment
    37Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2022-23600Feb 4, 2022 · Limited ability to spoof SAML authentication with missing audience verification
    26Monitor
  • ← EarlierCVE-2022-24841Apr 18, 2022 · Improper Authorization in github.com/fleetdm/fleet
    32Monitor
  • Later →CVE-2026-22808Jan 21, 2026 · Fleet Windows MDM endpoint has a Cross-site Scripting vulnerability
    22Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
fleetdm fleet4.64.2 · descriptionVendor (CNA)
Go:github.com/fleetdm/fleet/v44.53.2Package registry (OSV)
Go:github.com/fleetdm/fleet/v44.58.1Package registry (OSV)
Go:github.com/fleetdm/fleet/v44.62.4Package registry (OSV)
Go:github.com/fleetdm/fleet/v44.63.2Package registry (OSV)
Go:github.com/fleetdm/fleet/v44.64.2Package registry (OSV)

Exploit status

Proof of concept available

A public proof of concept or detection signature exists. Exploit knowledge is out there; don't delay patching.

Evidence

  • Proof-of-concept repository on GitHub ×1

Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.

Public exploit evidence
SourceKindDate
Proof-of-concept repository on GitHubstars:02026-10-21

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

  1. Published
  2. First PoC+593 d
  3. TodayNov 13, 2026+616 d

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Not on record for this CVE: EPSS history · researcher credit · variant or chain candidate · public bounty program.

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
Integrity
Availability
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
X

Weakness class (CWE)

CWE-285 · Improper Authorization

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/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-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

References

Show all references (1 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records