CVE-2025-63914
MediumCVSS 6.5Exploitation Probability (EPSS)
Low risk33th percentile - higher than 33% of all known CVEs
Summary
In Cinnamon kotaemon 0.11.0, the _may_extract_zip function in libs/ktem/ktem/index/file/ui.py does not check the contents of uploaded ZIP files. Although contents are extracted into a temporary folder, successfully uploading a ZIP bomb can still cause excessive resource consumption during decompression, and if no further files are uploaded, extracted data may occupy disk space and potentially render the system unavailable.
Risk Assessment
Anyone with file upload permission can perform a denial-of-service attack by exhausting server resources or filling disk space. This can disrupt service availability for all users.
Recommendation
Update kotaemon to a patched version or implement validation of ZIP archive contents before extraction (size, file count, compression ratio limits). Consider restricting file upload permissions.
Other vulnerabilities in kotaemon
See all- CVE-2026-69098Critical
Kotaemon through 0.12.0 contains an insecure deserialization vulnerability in the check_connection endpoint that allows unauthenticated attackers to instantiate arbitrary Python classes by supplying crafted YAML/JSON input with a __type__ field. Attackers can exploit this to override the __type__ field with subprocess.check_output and arbitrary arguments, achieving remote code execution with application process privileges.
- CVE-2026-86867Medium
Cinnamon's Kotaemon (all versions up to and including v0.12.0) multi-user chat interface contains multiple vulnerabilities due to incorrect authorization and improper access controls. There are four handler methods in `libs/ktem/ktem/pages/chat/control.py` that load a Conversation record by its ID without comparing the requester's `user_id` to the conversation's owner `Conversation.user`. This allows any authenticated user to perform the following actions: 1. Read other user's chat transcripts, RAG retrieval history, AI-generated plots, and chat suggestions. 2. Permanently delete another user's conversation. 3. Rename another user's conversation. 4. Overwrite another user's conversation's chat suggestion list.
- CVE-2026-82281High
Kotaemon through 0.12.0 fails to properly validate conversation ownership in select_conv, delete_conv, rename_conv, and on_set_public_conversation functions in control.py. Attackers can read other users' chat histories, delete conversations, or rename conversations by supplying arbitrary conversation identifiers without proper authorization checks.
- CVE-2025-56527High
Plaintext password storage in Kotaemon 0.11.0 in the client's localStorage. The flaw allows access to passwords through XSS attacks or physical access to the browser.
- CVE-2025-56526Medium
A cross-site scripting (XSS) vulnerability in Kotaemon 0.11.0 allows attackers to execute arbitrary code via a crafted PDF.
Original NVD description (English source)
An issue was discovered in Cinnamon kotaemon 0.11.0. The _may_extract_zip function in the \libs\ktem\ktem\index\file\ui.py file does not check the contents of uploaded ZIP files. Although the contents are extracted into a temporary folder that is cleared before each extraction, successfully uploading a ZIP bomb could still cause the server to consume excessive resources during decompression. Moreover, if no further files are uploaded afterward, the extracted data could occupy disk space and potentially render the system unavailable. Anyone with permission to upload files can carry out this attack.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS