CVE-2025-1257 Overview
CVE-2025-1257 is a denial of service vulnerability affecting GitLab Enterprise Edition (EE). The flaw exists in all versions starting with 12.3 before 17.7.7, 17.8 prior to 17.8.5, and 17.9 prior to 17.9.2. An unauthenticated attacker can manipulate specific API inputs to trigger a denial of service condition against vulnerable GitLab instances. The vulnerability is categorized under [CWE-770] (Allocation of Resources Without Limits or Throttling).
Critical Impact
Remote, unauthenticated attackers can disrupt GitLab service availability over the network without user interaction, impacting development pipelines and CI/CD operations.
Affected Products
- GitLab Enterprise Edition versions 12.3 through 17.7.6
- GitLab Enterprise Edition versions 17.8 through 17.8.4
- GitLab Enterprise Edition versions 17.9 through 17.9.1
Discovery Timeline
- 2025-03-13 - CVE-2025-1257 published to NVD
- 2025-08-08 - Last updated in NVD database
Technical Details for CVE-2025-1257
Vulnerability Analysis
The vulnerability resides in GitLab EE's API handling logic. Specific API inputs are not subject to adequate resource constraints or throttling. An attacker submits crafted requests over the network and forces the GitLab instance to consume excessive resources. The resulting condition degrades or halts service availability for legitimate users.
The issue impacts the availability of the GitLab instance. Confidentiality and integrity are not affected. Exploitation requires no authentication and no user interaction, making the attack surface broad for internet-facing GitLab deployments.
The Exploit Prediction Scoring System (EPSS) currently rates the probability of exploitation at 0.118%. No public proof-of-concept exploit is available, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog.
Root Cause
The root cause is improper resource allocation in API request handlers, classified as [CWE-770]. GitLab's affected endpoints fail to enforce limits on input size, processing time, or memory consumption. When attackers supply manipulated inputs, the application allocates resources without throttling, exhausting server capacity.
Attack Vector
The attack vector is network-based. An attacker sends crafted HTTP requests to vulnerable API endpoints on a reachable GitLab EE instance. Because no privileges or user interaction are required, scripted attacks against exposed GitLab servers are feasible. Refer to the GitLab Issue #519348 and the HackerOne Report #2984218 for technical specifics released by the vendor.
No verified exploitation code is available for this CVE. See the security advisory for technical details.
Detection Methods for CVE-2025-1257
Indicators of Compromise
- Sudden spikes in CPU, memory, or worker utilization on GitLab application servers without corresponding legitimate user activity.
- HTTP 5xx errors or request timeouts on GitLab API endpoints, particularly under sustained low-volume request patterns.
- Repeated requests from a small set of source IPs targeting specific API routes with anomalous payload sizes or parameter values.
Detection Strategies
- Review GitLab production.log and api_json.log for patterns of resource-intensive API calls correlated with degraded performance.
- Monitor reverse proxy and load balancer logs for elevated request rates against GitLab API paths from individual clients.
- Correlate Sidekiq queue depth, Puma worker saturation, and PostgreSQL connection counts against API request telemetry.
Monitoring Recommendations
- Forward GitLab application and web server logs to a centralized SIEM for correlation with system performance metrics.
- Alert on sustained anomalies in API response latency and 5xx error rates that exceed established baselines.
- Track outbound resource consumption per source IP and per API endpoint to identify abusive request patterns early.
How to Mitigate CVE-2025-1257
Immediate Actions Required
- Upgrade GitLab EE to version 17.7.7, 17.8.5, 17.9.2, or later as documented in the vendor advisory.
- Restrict network exposure of GitLab instances by placing them behind a VPN or IP-based access controls where feasible.
- Audit logs for prior signs of resource exhaustion attempts against API endpoints since GitLab 12.3 was deployed.
Patch Information
GitLab has released fixed versions 17.7.7, 17.8.5, and 17.9.2. Administrators running any affected version should apply the upgrade immediately. Patch details and remediation guidance are documented in GitLab Issue #519348.
Workarounds
- Apply rate limiting at the reverse proxy or web application firewall (WAF) layer for GitLab API endpoints.
- Configure GitLab's built-in user and IP rate limits to throttle anonymous and authenticated API traffic.
- Restrict API access to trusted networks until the upgrade is completed across all GitLab nodes.
# Configuration example - enable rate limiting in /etc/gitlab/gitlab.rb
gitlab_rails['rate_limit_requests_per_period'] = 300
gitlab_rails['rate_limit_period'] = 60
gitlab_rails['throttle_unauthenticated_api_enabled'] = true
gitlab_rails['throttle_unauthenticated_api_requests_per_period'] = 100
gitlab_rails['throttle_unauthenticated_api_period_in_seconds'] = 60
# Apply changes
sudo gitlab-ctl reconfigure
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
