External risk intelligence

Apache Allura Webhooks SSRF Vulnerability

CVE advisorySeverity: CRITICAL (CVSS 9.1)

CVE-2026-80181

Apache Allura is a web-based software forge platform that typically hosts project management and collaboration tools. Webhooks are a core, externally-facing feature of such systems, used to interact with third-party services over the internet. Consequently, this functionality is commonly exposed to public network traffic in standard deployments.

Server-Side Request Forgery

Halo Surface Signal: 4 out of 5 — likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

A Server-Side Request Forgery vulnerability has been identified in Apache Allura's webhooks. This technology is used for project management and collaboration tools, and the vulnerability could allow attackers to make unintended requests on behalf of the server. The main concern is confirming relevance and exposure.

Webhooks can be tricked into making unintended server requests.
This affects collaboration tools, potentially impacting data access.
Confirming exposure is the immediate leadership concern.

Attack Path

How an attacker could exploit the issue

An attacker could exploit this vulnerability by sending a specially crafted request to the webhooks feature of Apache Allura. This could allow them to trick the server into making requests to internal or external resources, potentially leading to unauthorized access to sensitive information or other systems.

No authentication required to access.
Triggered by sending a crafted webhook request.
Risk of unauthorized server requests.

Live Threat

Current exploitation, exposure, and threat context

This vulnerability could allow an unauthenticated attacker to make the Allura server issue requests to arbitrary internal or external network resources when supported by the advisory's configuration.

Server requests to arbitrary hosts.
Webhooks could trigger unintended requests.
Potential for unauthorized internal access.

Operational Fix

Recommended remediation, mitigation, and detection steps

The SSRF vulnerability in Apache Allura webhooks requires immediate attention from application owners and platform teams. The first practical step is to identify all instances of affected Allura deployments, determine their internet reachability and business criticality, and confirm the responsible system owner for prompt remediation planning.

Application and platform teams own remediation.
Verify Allura deployment reachability and criticality.
Plan remediation based on identified risk.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

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Frequently asked questions

What is Apache Allura?

Apache Allura is an open-source, web-based platform designed for project hosting and collaboration. It provides tools for software development, such as issue tracking, code repositories, and documentation management. By hosting these services, it allows teams to coordinate development tasks and manage project workflows in a centralized, web-accessible environment.

How does CVE-2026-80181 create a Server-Side Request Forgery weakness?

This vulnerability is classified as CWE-918: Server-Side Request Forgery (SSRF). In plain terms, it means an attacker can manipulate the application to send requests to destinations of their choosing. Because the server itself initiates these requests, it may bypass security controls, allowing the attacker to interact with internal or external resources that would otherwise be protected or inaccessible to them directly.

What triggers the SSRF vulnerability in these webhooks?

The flaw is triggered when an attacker sends a specially crafted request to the webhooks feature within the platform. Because this specific endpoint does not require authentication, an attacker can initiate these malicious requests without needing a valid user account. Simply interacting with other, non-webhook parts of the application does not trigger this specific vulnerability.

Is my Apache Allura instance at risk?

According to Halo Surface Signal, Apache Allura is a platform for collaboration that relies on webhooks as a core, externally-facing feature. Because webhooks are designed to communicate with other services over the internet, your instance is more likely to be reachable by public network traffic. If your deployment is exposed to the internet, you should consider it a priority for investigation.

How should I respond to this vulnerability?

The primary step is to identify all running instances of Apache Allura within your environment. Once identified, document which systems are internet-facing versus internal to help prioritize your efforts. Finally, plan for an update to version 1.21.0, as this release includes the necessary fixes to resolve the SSRF vulnerability in the webhooks component.

References

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.