Debian Jupyter-Server vulnerabilities

CVE-2026-35397 [HIGH] CWE-22 Jupyter Server: Path Traversal via incorrect startswith() root directory check allows access to sibling directories Jupyter Server: Path Traversal via incorrect startswith() root directory check allows access to sibling directories ### Summary Jupyter Server <=2.17.0 can access directories sibling to the root directory, if it starts with the root dir's name. ### PoC Minimal: ``` . ├── test/ <- root directory. │ └── test.txt └── testtest/ └── secret.txt <- file t

CVE-2026-6657 [MEDIUM] CWE-346 jupyter-server is vulnerable to CORS origin validation bypass when the `allow_origin_pat` configuration is used jupyter-server is vulnerable to CORS origin validation bypass when the `allow_origin_pat` configuration is used A vulnerability in jupyter-server versions 1.12.0 through 2.17.0 allows an attacker to bypass CORS origin validation when the `allow_origin_pat` configuration is used. The issue arises from the use of `re.match()` for validating the `Origin` he

CVE-2026-5422 [MEDIUM] CWE-23 Jupyter Server vulnerable to Path Traversal via incorrect root directory boundary check in _get_os_path() Jupyter Server vulnerable to Path Traversal via incorrect root directory boundary check in _get_os_path() A path traversal vulnerability exists in jupyter-server version 2.17.0 due to an incorrect root directory boundary check in the _get_os_path() function within jupyter_server/services/contents/fileio.py. The check uses startswith(root) without appending a tr

CVE-2026-114135 [HIGH] CWE-862 Jupyter Server: Gateway WebSocket handler bypasses kernel execute authorization Jupyter Server: Gateway WebSocket handler bypasses kernel execute authorization ### Summary Jupyter Server's gateway WebSocket handler checks that a user is authenticated, but it does not ask the configured Authorizer whether that user may execute kernels. In Jupyter Server 2.0.0 through 2.5.0, enabling GatewayClient.url automatically replaced the normal kernel channel handler with t

CVE-2022-29241 [HIGH] CVE-2022-29241: jupyter-server - Jupyter Server provides the backend (i.e. the core services, APIs, and REST endp... Jupyter Server provides the backend (i.e. the core services, APIs, and REST endpoints) for Jupyter web applications like Jupyter Notebook. Prior to version 1.17.1, if notebook server is started with a value of `root_dir` that contains the starting user's home directory, then the underlying REST API can be used to leak the access token assigned at start time b

CVE-2026-40934 [MEDIUM] CWE-613 Jupyter Server's Authentication Cookies Remain Valid After Password Reset and Server Restart Jupyter Server's Authentication Cookies Remain Valid After Password Reset and Server Restart ## Summary A persistent cookie secret vulnerability allows authenticated users to maintain indefinite access even after password changes. The cookie secret used to sign authentication cookies is stored in a permanent file (`~/.local/share/jupyter/runtime/jupyter_cookie_secret`)

CVE-2022-24757 [HIGH] CVE-2022-24757: jupyter-server - The Jupyter Server provides the backend (i.e. the core services, APIs, and REST ... The Jupyter Server provides the backend (i.e. the core services, APIs, and REST endpoints) for Jupyter web applications. Prior to version 1.15.4, unauthorized actors can access sensitive information from server logs. Anytime a 5xx error is triggered, the auth cookie and other header values are recorded in Jupyter Server logs by default. Considering these logs

CVE-2026-40110 [HIGH] CWE-777 Jupyter Server has a CORS Origin Validation Bypass via `re.match()` in `allow_origin_pat` (from huntr) Jupyter Server has a CORS Origin Validation Bypass via `re.match()` in `allow_origin_pat` (from huntr) Jupyter Server uses `re.match()` to validate the Origin header against the `allow_origin_pat` configuration. Since `re.match()` only anchors at the start of the string, an attacker who controls a domain like `http://trusted.example.com.evil.com/` passes validat

CVE-2026-44727 [CRITICAL] CWE-1021 Jupyter Server: Stored XSS in `NbconvertFileHandler` / `NbconvertPostHandler` via missing `sandbox` CSP Jupyter Server: Stored XSS in `NbconvertFileHandler` / `NbconvertPostHandler` via missing `sandbox` CSP The nbconvert HTTP handlers in jupyter_server render user-authored notebook HTML under the Jupyter origin without a sandbox directive in their `Content-Security-Policy`. Combined with `nbconvert.HTMLExporter`'s default non-sanitizing behavior, a notebook

CVE-2023-40170 [MEDIUM] CVE-2023-40170: jupyter-server - jupyter-server is the backend for Jupyter web applications. Improper cross-site ... jupyter-server is the backend for Jupyter web applications. Improper cross-site credential checks on `/files/` URLs could allow exposure of certain file contents, or accessing files when opening untrusted files via "Open image in new tab". This issue has been addressed in commit `87a49272728` which has been included in release `2.7.2`. Users are advised to

CVE-2023-39968 [MEDIUM] CVE-2023-39968: jupyter-server - jupyter-server is the backend for Jupyter web applications. Open Redirect Vulner... jupyter-server is the backend for Jupyter web applications. Open Redirect Vulnerability. Maliciously crafted login links to known Jupyter Servers can cause successful login or an already logged-in session to be redirected to arbitrary sites, which should be restricted to Jupyter Server-served URLs. This issue has been addressed in commit `29036259` which is

CVE-2025-61669 [MEDIUM] CWE-601 Jupyter Server has an open redirection vulnerability in `next` query parameter Jupyter Server has an open redirection vulnerability in `next` query parameter ### Summary The `?next=...` URL query parameter has an open redirection vulnerability. In `jupyter_server<=2.17.0`, this URL query parameter allows redirection to arbitrary external domains, which can be exploited to facilitate phishing attacks on server users. ### Details The vulnerability is caused by i

CVE-2020-26275 [MEDIUM] CVE-2020-26275: jupyter-server - The Jupyter Server provides the backend (i.e. the core services, APIs, and REST ... The Jupyter Server provides the backend (i.e. the core services, APIs, and REST endpoints) for Jupyter web applications like Jupyter notebook, JupyterLab, and Voila. In Jupyter Server before version 1.1.1, an open redirect vulnerability could cause the jupyter server to redirect the browser to a different malicious website. All jupyter servers running witho

CVE-2020-26232 [MEDIUM] CVE-2020-26232: jupyter-server - Jupyter Server before version 1.0.6 has an Open redirect vulnerability. A malici... Jupyter Server before version 1.0.6 has an Open redirect vulnerability. A maliciously crafted link to a jupyter server could redirect the browser to a different website. All jupyter servers are technically affected, however, these maliciously crafted links can only be reasonably made for known jupyter server hosts. A link to your jupyter server may appear s

CVE-2023-49080 [LOW] CVE-2023-49080: jupyter-server - The Jupyter Server provides the backend (i.e. the core services, APIs, and REST ... The Jupyter Server provides the backend (i.e. the core services, APIs, and REST endpoints) for Jupyter web applications like Jupyter notebook, JupyterLab, and Voila. Unhandled errors in API requests coming from an authenticated user include traceback information, which can include path information. There is no known mechanism by which to trigger these errors w