CVE-2024-39933: Gogs Argument Injection Vulnerability

CVE-2024-39933 Overview

CVE-2024-39933 is an argument injection vulnerability in Gogs, a self-hosted Git service written in Go. The flaw affects all versions of Gogs through 0.13.0 and occurs during the tagging of a new release. Authenticated attackers can inject arguments into the underlying Git command invoked by the release tagging workflow. Exploitation requires low privileges and no user interaction, and it can be triggered over the network. The issue is tracked under CWE-88: Improper Neutralization of Argument Delimiters in a Command.

Critical Impact
Authenticated users with permission to create releases can inject Git command arguments, exposing sensitive file contents from the Gogs server and enabling scope-changing information disclosure across tenants.

Affected Products

Gogs versions through 0.13.0
Self-hosted Gogs Git service instances
Any Gogs deployment permitting authenticated users to create release tags

Discovery Timeline

2024-07-04 - CVE-2024-39933 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2024-39933

Vulnerability Analysis

Gogs invokes the git binary as a subprocess to perform repository operations, including tagging a new release. The release tagging code path passes user-controlled input into the Git command line without correctly separating options from positional arguments. Because Git treats tokens beginning with - or -- as options, an attacker can supply a crafted tag name or related field that Git interprets as a flag rather than data.

The vulnerability sits in the category of argument injection rather than shell command injection. No shell metacharacter escaping is bypassed. Instead, the attacker abuses Git's own option parser to redirect its behavior, for example by supplying options that cause Git to read arbitrary files or emit their contents into the resulting output. The Sonar research team documented the class of issue in their analysis of unpatched Gogs vulnerabilities.

Root Cause

The root cause is missing use of the -- end-of-options separator and insufficient validation of tag-related inputs before they are appended to the git command line. Gogs treats attacker-controlled strings as trusted argv entries, allowing them to occupy the option position of the Git invocation.

Attack Vector

An authenticated user with permission to create a release in any repository they can write to triggers the tag-creation flow with a crafted value. The scope of impact extends beyond the attacker's own repository because injected Git options can cause the server-side process to read files outside the intended repository context, resulting in confidentiality loss on the host running Gogs. Refer to the Sonar security advisory for the exploitation walkthrough.

No verified public proof-of-concept code has been released. See the Sonar security advisory for a description of the exploitation primitive.

Detection Methods for CVE-2024-39933

Indicators of Compromise

Release or tag creation events where the tag name begins with - or --, or contains Git long options such as --upload-pack, --output, or --exec
Gogs process logs showing git tag, git archive, or related invocations with unexpected option-shaped arguments before the -- separator
Access to files outside a repository's working directory by the Gogs service account correlated with release tag events

Detection Strategies

Parse Gogs audit logs and web access logs for POST requests to release-creation endpoints containing tag values beginning with a dash
Monitor execve syscalls from the Gogs process on Linux hosts for git invocations that include option-like tokens in positions reserved for tag names or refs
Alert on unexpected reads of sensitive paths such as /etc/passwd, SSH keys, or Gogs configuration by the Gogs service user

Monitoring Recommendations

Enable verbose request logging on the Gogs application and forward events to a centralized log platform for retention and correlation
Baseline normal tag naming conventions in your environment and alert on deviations, particularly leading-dash patterns
Correlate release-creation events with subsequent outbound network activity or file reads from the Gogs host

How to Mitigate CVE-2024-39933

Immediate Actions Required

Inventory all Gogs instances and confirm the running version; treat any deployment at or below 0.13.0 as vulnerable
Restrict repository write and release-creation permissions to trusted users until a fix is applied
Place internet-facing Gogs behind an authenticated reverse proxy or VPN to reduce the attacker population

Patch Information

At the time of publication, no fixed release was identified in the CVE record. Monitor the Gogs releases page on GitHub for a patched version and review the Sonar research on unpatched Gogs vulnerabilities for context on remediation status. Organizations that require a supported alternative should evaluate migration to actively maintained self-hosted Git platforms.

Workarounds

Disable release creation for untrusted users through repository role configuration where feasible
Run Gogs under a dedicated low-privilege service account with filesystem access limited to its own data directory
Apply mandatory access controls such as AppArmor or SELinux profiles to constrain what the Gogs process can read on the host
Deploy a web application firewall rule that rejects release-creation requests carrying tag names beginning with -

bash

# Example WAF-style rule to block dash-prefixed tag names in Gogs release creation
# Applied at reverse proxy in front of Gogs
location ~ ^/[^/]+/[^/]+/releases/new$ {
    if ($arg_tag_name ~ "^-") { return 403; }
    if ($request_body ~ "tag_name=-") { return 403; }
    proxy_pass http://gogs_upstream;
}