What is the CVSS score of CVE-2023-49091?

CVE-2023-49091 has a CVSS 3.1 base score of 9.8 (Critical). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.8%.

Is there a public PoC exploit available for CVE-2023-49091?

Yes, a public proof-of-concept exploit is available for CVE-2023-49091. Prioritise patching immediately. EPSS: 0.8%.

Is there a patch available for CVE-2023-49091?

Yes, a patch is available for CVE-2023-49091. Update the affected software to the latest version immediately.

Cosmos Server CVE-2023-49091

CRITICAL

Insufficient Session Expiration (CWE-613)

2023-11-29 security-advisories@github.com

Authentication Bypass Cosmos Server

9.8

CVSS 3.1 · NVD

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Vulnerability Assessment

Weakness	CWE CWE-613 OWASP Top 10:2025 A07:2025 - Authentication Failures ASVS 5.0 V7 - Session Management Session expiration enforcement
Impact	CVSS score of 9.8 (CRITICAL). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. Public proof-of-concept exploit code is available.
Exploit ScenarioDerived	This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the critical-severity affected system.

Act Now Prioritize within 24-48h. Why: CRITICAL severity + public POC available.

Patch available 0.8% exploitation probability (EPSS)

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AnalysisAI

Cosmos provides users the ability self-host a home server by acting as a secure gateway to your application, as well as a server manager. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.

Affects your stack

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Technical ContextAI · show details

This vulnerability is classified under CWE-613. Cosmos provides users the ability self-host a home server by acting as a secure gateway to your application, as well as a server manager. Cosmos-server is vulnerable due to to the authorization header used for user login remaining valid and not expiring after log out. This vulnerability allows an attacker to use the token to gain unauthorized access to the application/system even after the user has logged out. This issue has been patched in version 0.13.1. Affected products include: Cosmos-Cloud Cosmos Server. Version information: version 0.13.1..

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Exploit and PoC references, threat intelligence from 22 sources

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Severity by source

NVD PRIMARY 9.8 CRITICAL

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

DescriptionNVD

Cosmos provides users the ability self-host a home server by acting as a secure gateway to your application, as well as a server manager. Cosmos-server is vulnerable due to to the authorization header used for user login remaining valid and not expiring after log out. This vulnerability allows an attacker to use the token to gain unauthorized access to the application/system even after the user has logged out. This issue has been patched in version 0.13.1.

Threat Intelligence Overview

EPSS Score

0.8%

Top 49% exploitable

Exploit

POC

Public exploit code exists

Data Quality

3 sources

Confidence: Low

NVD

CVE.org

EPSS

GitHub

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue

Severity CRITICAL

CISA KEV No

Public POC Yes

EPSS 0.8%

Patch available Yes

Active threat No

Deciding rule

CRITICAL severity + public POC available

What every action level means

Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.

Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.

This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.

This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.

Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.