CVE-2026-58508 in Gitea
Summary
by MITRE • 08/13/2026
Two SSRF vulnerabilities in Gitea migration/mirror (DNS rebinding + missing re-validation)
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Analysis
by VulDB Data Team • 08/13/2026
Gitea migration and mirror functionality contains two critical server-side request forgery vulnerabilities that can be exploited to bypass security controls and access internal systems. The first vulnerability stems from DNS rebinding attacks during the migration process where the application fails to properly validate domain names and resolves them without adequate restrictions. This allows attackers to manipulate DNS responses and redirect requests to internal services that should remain inaccessible from external networks. The second vulnerability occurs due to missing re-validation of user-provided URLs during mirror synchronization, where input validation is performed only once at the initial stage but not re-validated when processing subsequent requests. Both vulnerabilities fall under CWE-918 Server-Side Request Forgery and align with ATT&CK technique T1190 for exploitation through server-side request forgery. The technical flaw exploits the trust relationship between Gitea's internal services and external endpoints, enabling attackers to perform unauthorized access to internal resources such as databases, internal APIs, or other network services that are typically protected by firewalls or network segmentation. When combined, these vulnerabilities create a potent attack vector where an attacker can first establish a DNS rebinding condition through the migration process and then leverage the missing re-validation during mirror operations to access sensitive internal systems.
The operational impact of these vulnerabilities extends beyond simple data theft or service disruption, as they enable attackers to potentially gain persistent access to internal network resources. An attacker could use the DNS rebinding capability to bypass firewall restrictions and directly connect to internal services that would normally be unreachable from the internet. The missing re-validation during mirror operations allows for continuous exploitation where attackers can manipulate URLs multiple times throughout the synchronization process, increasing their chances of success and potentially gaining access to more sensitive systems over time. This vulnerability chain particularly affects organizations that rely on Gitea for code repository management and automated mirroring between internal and external systems, as it undermines the security boundaries established by network architecture. The attack surface is further expanded when considering that many organizations use Gitea in environments where internal services are not properly isolated from external access points, making these vulnerabilities even more dangerous.
Mitigation strategies should focus on implementing strict input validation and sanitization at multiple stages of the migration and mirroring processes. Organizations must enforce proper URL validation that includes domain name restrictions, IP address range checks, and DNS resolution controls to prevent DNS rebinding attacks. The application should implement re-validation mechanisms that ensure all user-provided URLs are checked against security policies at every stage of processing rather than relying on single validation points. Network segmentation controls should be enhanced to limit access between internal services and external endpoints, while implementing proper firewall rules to restrict outbound connections from Gitea instances to known good destinations only. Additionally, organizations should consider implementing DNS filtering mechanisms that prevent resolution of internal IP ranges or private addresses through public DNS queries. The implementation of these mitigations aligns with security best practices outlined in NIST SP 800-53 and ISO 27001 standards for access control and network security. Regular security testing including penetration testing and vulnerability scanning should be conducted to identify similar issues in other applications that may be vulnerable to the same class of server-side request forgery attacks, particularly those involving automated service interactions or external resource resolution processes.