CVE-2025-51865: IDOR Vulnerability Exposes AI2 Playground LLM Chat Data
Welcome to a deep dive into CVE-2025-51865, a recently discovered vulnerability affecting the AI2 Playground web service (playground.allenai.org). This post will break down the flaw, its potential impact, and what you need to know.
🔍 TL;DR Summary
CVE-2025-51865 is an Insecure Direct Object Reference (IDOR) vulnerability in the AI2 Playground's LLM chat feature, active until June 3, 2025. By manipulating thread keys in URLs, attackers could potentially access sensitive information from other users' chat sessions. This vulnerability highlights the importance of proper authorization and secure object handling in web applications.
🚨 Vulnerability Details
- CVE ID: CVE-2025-51865
- Description: The Ai2 playground web service (playground.allenai.org) LLM chat through 2025-06-03 is vulnerable to Insecure Direct Object Reference (IDOR), allowing attackers to gain sensitive information via enumerating thread keys in the URL.
- CVSS Score: 8.8 HIGH
- CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- CVSS Explanation:
- AV:N (Network): The vulnerability can be exploited over a network.
- AC:L (Low): The attack does not require special conditions and can be launched easily.
- PR:N (None): No privileges are required to exploit the vulnerability.
- UI:R (Required): User interaction is required for the attack to be successful (e.g., clicking a malicious link).
- S:U (Unchanged): The vulnerability affects only the component it resides in.
- C:H (High): There is a high impact on confidentiality; sensitive data could be exposed.
- I:H (High): There is a high impact on integrity; data can be modified.
- A:H (High): There is a high impact on availability; the system could become unavailable.
- Exploit Requirements: User needs to be tricked into clicking a specially crafted link, but exploitation itself is straightforward.
- Affected Vendor: AllenAI
- Affected Product: Ai2 Playground (LLM Chat)
- Affected Version: Through 2025-06-03
- CWE: CWE-639 - Authorization Bypass Through User-Controlled Key: This CWE describes a vulnerability where an attacker can bypass authorization by manipulating a key or identifier that is used to access resources.
📅 Timeline of Events
- 2025-06-03: Vulnerability Window Closes
- 2025-07-22: CVE ID Assigned and Published
🧠 Exploitability & Real-World Risk
The real-world risk of CVE-2025-51865 is moderate to high. While user interaction is required, attackers could use social engineering tactics to trick users into clicking malicious links. A successful exploit could lead to the disclosure of sensitive chat logs, potentially including personal information or confidential discussions. Given the nature of LLM interactions, the exposed data could be quite valuable.
🛠️ Recommendations
Since the vulnerability window has closed (2025-06-03), it's assumed that AllenAI has patched the issue. However, general best practices include:
- Always practice safe browsing habits. Be cautious of suspicious links and avoid clicking on anything from unknown sources.
- Verify the authenticity of URLs. Before clicking a link, double-check the domain and path to ensure it leads to the intended destination.
- Developers should implement proper authorization checks. Ensure that users can only access resources they are explicitly authorized to view.
🧪 Technical Insight
The vulnerability stems from the predictable or enumerable nature of thread keys used in the AI2 Playground's LLM chat feature. Without proper authorization checks, an attacker could simply modify the thread key in the URL to access other users' chat sessions. This is a classic example of an IDOR vulnerability, where the application relies on user-supplied input to directly access objects without validating the user's permissions.
🙌 Credit to Researcher(s)
This vulnerability was discovered by Secsys-FDU.
🔗 References
🧵 Tags
#CVE-2025-51865 #IDOR #AI2Playground #LLMChat #Vulnerability #Security #DataBreach #AllenAI
Summary: CVE-2025-51865 is an IDOR vulnerability in the AI2 Playground LLM chat, allowing attackers to access sensitive chat data by manipulating thread keys in URLs. The vulnerability highlights the importance of proper authorization checks and secure object handling in web applications.
CVE ID: CVE-2025-51865
Risk Analysis: Successful exploitation could lead to the exposure of sensitive information contained within the LLM chat sessions, potentially including personal details, confidential discussions, or intellectual property. This could result in reputational damage, legal liabilities, and financial losses for affected users.
Recommendation: Users should exercise caution when clicking links and ensure they are accessing the intended resource. Developers should implement robust authorization checks to prevent unauthorized access to resources.
Timeline
- 2025-06-03: End date for vulnerable LLM chat service
- 2025-07-22: CVE-2025-51865 assigned and published