CVE-2025-9803Network attack vector

Account takeover via unchecked OAuth token audience

Published Nov 25, 2025 · Updated Nov 25, 2025

Improper authentication in Lunary before 1.9.35 allows remote attackers to take over accounts through a Google OAuth access token. The Google OAuth callback accepts an access token without confirming that its aud claim names the Lunary client, so a token issued to an attacker-controlled application is treated as valid. A victim must authorize the malicious Google application; the resulting token lets the attacker sign in as that victim and access or alter the victim's Lunary data.

CVSS severity9.3
Critical
EPSS probability0.47%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Improper authentication in Lunary before 1.9.35 allows remote attackers to take over accounts through a Google OAuth access token. The Google OAuth callback accepts an access token without confirming that its aud claim names the Lunary client, so a token issued to an attacker-controlled application is treated as valid. A victim must authorize the malicious Google application; the resulting token lets the attacker sign in as that victim and access or alter the victim's Lunary data.

The record

CVE
CVE-2025-9803
Published
Nov 25, 2025
Updated
Nov 25, 2025
Vendor
Lunary
Product
Lunary
Classifications
CWE-287, CWE-863, T1078
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 25, 2025CVE publishedPublication date reported by the CVE source.
  2. Nov 25, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <1.9.35

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Lunary · Lunaryversion=unspecified <1.9.35

Published CVSS scores

8.8NISTCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
9.3huntr.devCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-287Improper Authentication
CWE-863Incorrect Authorization
T1078Valid Accounts

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo