grist-core: Improper Neutralization of Special Elements in Output Used by a Downstream Component
CVE-2026-24002 is a critical-severity improper neutralization of special elements in output used by a downstream component vulnerability in grist-core from Gristlabs, with a CVSS 3.1 base score of 9.6 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. Affected grist-core versions: < 1.7.9. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.52% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of grist-core 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.
- Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Gristlabs | grist-core | < 1.7.9 | Not stated |
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.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- RequiredA user must take an action such as opening a file or link.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 9.0 | Critical | CNA (github.com) |
| CVSS 3.1 | 9.6 | Critical | NVD |
Official description
Grist is spreadsheet software using Python as its formula language. Grist offers several methods for running those formulas in a sandbox, for cases where the user may be working with untrusted spreadsheets. One such method runs them in pyodide, but pyodide on node does not have a useful sandbox barrier. If a user of Grist sets `GRIST_SANDBOX_FLAVOR` to `pyodide` and opens a malicious document, that document could run arbitrary processes on the server hosting Grist. The problem has been addressed in Grist version 1.7.9 and up, by running pyodide under deno. As a workaround, a user can use the gvisor-based sandbox by setting `GRIST_SANDBOX_FLAVOR` to `gvisor`.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Neutralization of Special Elements in Output Used by a Downstream Component
The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component.
How developers prevent this class of flaw
- Programming languages and supporting technologies might be chosen which are not subject to these issues.
- Utilize an appropriate mix of allowlist and denylist parsing to filter control-plane syntax from all input.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other vulnerabilities in grist-core
- 8.5 High severity
- 7.7 High severity
Recent Improper Neutralization of Special Elements in Output Used by a Downstream Component vulnerabilities
- 8.8 High severity
- 8.8 High severity
- 7.3 High severity
- 9.8 Critical severity
- 8.8 High severity
- 8.8 High severity
Spotted an error? Tell us.