nixpkgs: Insertion of Sensitive Information into Externally-Accessible File or Directory
CVE-2026-23838 is a high-severity insertion of sensitive information into externally-accessible file or directory vulnerability in nixpkgs from NixOS, with a CVSS 4.0 base score of 8.7 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected nixpkgs versions: >= 23.05, < 26.05. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.51% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of nixpkgs you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Attack requirements
- NoneThe attack does not depend on a particular deployment or configuration.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Confidentiality (vulnerable system)
- HighSerious loss of confidentiality on the vulnerable system.
- Integrity (vulnerable system)
- NoneNo loss of integrity on the vulnerable system.
- Availability (vulnerable system)
- NoneNo loss of availability on the vulnerable system.
- Confidentiality (other systems)
- NoneNo loss of confidentiality on systems beyond the vulnerable one.
- Integrity (other systems)
- NoneNo loss of integrity on systems beyond the vulnerable one.
- Availability (other systems)
- NoneNo loss of availability on systems beyond the vulnerable one.
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. Scored by CNA (github.com).
Official description
Tandoor Recipes is a recipe manager than can be installed with the Nix package manager. Starting in version 23.05 and prior to version 26.05, when using the default configuration of Tandoor Recipes, specifically using SQLite and default `MEDIA_ROOT`, the full database file may be externally accessible, potentially on the Internet. The root cause is that the NixOS module configures the working directory of Tandoor Recipes, as well as the value of `MEDIA_ROOT`, to be `/var/lib/tandoor-recipes`. This causes Tandoor Recipes to create its `db.sqlite3` database file in the same directory as `MEDIA_ROOT` causing it to be accessible without authentication through HTTP like any other media file. This is the case when using `GUNICORN_MEDIA=1` or when using a web server like nginx to serve media files. NixOS 26.05 changes the default value of `MEDIA_ROOT` to a sub folder of the data directory. This only applies to configurations with `system.stateVersion` >= 26.05. For older configurations, one of the workarounds should be applied instead. NixOS 25.11 has received a backport of this patch, though it doesn't fix this vulnerability without user intervention. A recommended workaround is to move `MEDIA_ROOT` into a subdirectory. Non-recommended workarounds include switching to PostgreSQL or disallowing access to `db.sqlite3`.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Insertion of Sensitive Information into Externally-Accessible File or Directory
The product places sensitive information into files or directories that are accessible to actors who are allowed to have access to the files, but not to the sensitive information.
How developers prevent this class of flaw
- Do not expose file and directory information to the user.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other references
Other vulnerabilities in nixpkgs
- 8.5 High severity
- 9.1 Critical severity
- 8.8 High severity
Recent Insertion of Sensitive Information into Externally-Accessible File or Directory vulnerabilities
- 8.8 High severity
- 7.3 High severity
- 9.8 Critical severity
- 7.5 High severity
Spotted an error? Tell us.