CVE-2025-64111: Critical Gogs Flaw Lets Remote Attackers Bypass Authorization and Execute Code on Servers

Overview

CVE-2025-64111 is a critical authorization bypass leading to remote code execution (RCE) vulnerability identified in Gogs, a self-hosted Git service. The issue exists due to improper validation of repository write operations, allowing restricted Git internal paths to be modified remotely. By abusing this weakness, arbitrary commands can be executed on the underlying server.

This vulnerability is considered highly dangerous because it affects a core function of the application and can be exploited remotely with low complexity.

CVE Details (At a Glance)

Field	Details
CVE ID	CVE-2025-64111
Affected Product	Gogs
Vulnerability Type	Authorization Bypass → Remote Code Execution
Attack Vector	Network
Attack Complexity	Low
Privileges Required	None / Improperly enforced
User Interaction	None
Impact	Full system compromise
CVSS Score (Base)	9.3
Severity	Critical
Exploitability	High
Exploit Availability	No official public PoC released (exploitation feasible and reproducible for educational purposes)

Affected Versions

All Gogs versions prior to 0.13.4
Development builds prior to 0.14.0+dev

Root Cause Analysis

The vulnerability is caused by insufficient authorization and path validation during repository content update operations. Certain API endpoints responsible for writing repository files fail to correctly block access to internal Git directories such as .git/.

As a result, it becomes possible for crafted requests to:

Write or overwrite files inside .git/
Modify sensitive Git metadata such as configuration files or hooks
Introduce executable content that later gets triggered by Git operations

This flaw effectively breaks the trust boundary between repository content and Git internals.

Exploitation Flow

The vulnerability can be exploited in the following manner:

A vulnerable Gogs instance is identified and reached over the network.
A specially crafted HTTP request is sent to a repository content update API endpoint.
The request includes a file path pointing to a Git internal location (e.g., .git/config or .git/hooks/).
Due to missing authorization checks, the write operation succeeds.
Malicious content is placed in Git internals.
When Git operations are triggered, the malicious content is executed on the host system.
Arbitrary commands run with the privileges of the Gogs service account.

This results in remote code execution and potential full server takeover.

Proof of Concept / Exploitation Status

No official exploit code has been published by the vendor. However:

The exploitation technique is well understood.
Similar historical vulnerabilities in Git-based platforms have been weaponized.
The required steps involve standard HTTP requests and file writes.

For educational and defensive testing purposes, exploitation can be reproduced by simulating malicious writes to .git paths via affected API endpoints. Due to the low complexity and high impact, exploitation should be assumed possible in real-world scenarios.

MITRE Mapping

CWE

CWE-78 – Improper Neutralization of Special Elements used in an OS Command
CWE-284 – Improper Access Control

ATT&CK Techniques

T1190 – Exploit Public-Facing Application
T1059 – Command and Scripting Interpreter
T1505 – Server Software Component

Impact

If successfully exploited, the following impacts may occur:

Execution of arbitrary system commands
Deployment of web shells or backdoors
Unauthorized access to source code repositories
Credential theft
Lateral movement within the environment
Persistence through Git hooks or scheduled tasks

Detection & Monitoring

Recommended Log Sources

Web server access logs (Nginx / Apache)
Gogs application logs
Host process execution logs
File integrity monitoring data
Network egress logs

Detection Queries

Splunk – Suspicious Repository Writes

index=web_logs method IN ("POST","PUT")
uri_path="/api/v1/repos"
(request_body="*.git/*" OR request_body="*.git/config" OR request_body="*.git/hooks*")

Elastic / OpenSearch – Git Internal Path Abuse

http.request.method : ("POST" or "PUT") and
url.path : "/api/v1/repos" and
request.body : "*\.git/*"

Linux Host – Recently Modified Git Internals

find /var/lib/gogs -path "*/.git/*" -type f -mtime -7 -ls

Process Execution Monitoring

ps aux | grep gogs

Look for unexpected child processes such as shells, curl, wget, or netcat spawned by the Gogs service account.

Indicators of Compromise

Modification timestamps on .git/config or .git/hooks/*
Unexpected executable permissions on repository files
Outbound connections from the Gogs server to unknown IP addresses
Presence of shell commands inside Git hook files
Sudden creation of new system users or scheduled jobs

Remediation & Mitigation

Immediate Actions

Upgrade to a patched version immediately.
Restrict external access to repository write APIs until patched.
Perform a compromise assessment if exposure is confirmed.

Long-Term Hardening

Enable file integrity monitoring on repository directories.
Restrict execution permissions where not required.
Monitor outbound traffic from the Gogs host.
Isolate Gogs in a restricted container or sandboxed environment.

Official Patch / Upgrade Link

Gogs Security Advisory and Fixed Releases (Official Source):
https://github.com/gogs/gogs/security/advisories/GHSA-gg64-xxr9-qhjp

Final Takeaway

CVE-2025-64111 represents a high-confidence, high-impact security risk. Due to the nature of Git internals and the trust placed on repository metadata, exploitation can quickly escalate from a simple API abuse to complete server compromise. Systems running vulnerable versions should be considered unsafe until patched and verified.