@tinacms/mdx before 2.4.2 Code Injection via MDX Serializer Rich-Text Values
Summary
| CVE | CVE-2026-126774 |
|---|---|
| State | PUBLISHED |
| Assigner | VulnCheck |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-11-11 19:17:37 UTC |
| Updated | 2026-11-11 19:17:37 UTC |
| Description | @tinacms/mdx before 2.4.2 contains a code injection vulnerability in its MDX serializer, which writes rich-text values into MDX expressions without escaping them. Authenticated content editors can save crafted values that break out of list field or highlightColor expressions in the stored .mdx file, executing JavaScript in visitors' browsers or on build and server-side rendering hosts. |
Risk And Classification
Primary CVSS: v4.0 8.8 HIGH from [email protected]
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/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
Problem Types: CWE-94 | CWE-94 Improper Control of Generation of Code ('Code Injection')
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | [email protected] | Secondary | 8.8 | HIGH | CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N/E:X/C... |
| 4.0 | CNA | CVSS | 8.8 | HIGH | CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N |
| 3.1 | [email protected] | Primary | 8.2 | HIGH | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:N |
| 3.1 | CNA | CVSS | 8.2 | HIGH | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:N |
CVSS v4.0 Breakdown
Attack Vector
NetworkAttack Complexity
LowAttack Requirements
PresentPrivileges Required
LowUser Interaction
NoneConfidentiality
HighIntegrity
HighAvailability
NoneSub Conf.
HighSub Integrity
HighSub Availability
NoneCVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/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
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
HighPrivileges Required
LowUser Interaction
NoneScope
ChangedConfidentiality
HighIntegrity
HighAvailability
NoneCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:N
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Tinacms | @tinacms/mdx | affected 2.4.2 semver | Not specified |
| CNA | Tinacms | @tinacms/mdx | unaffected 2.4.2 semver | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/tinacms/tinacms/commit/19285c6deeee52c380e8b2fdeafedc9530dc0618 | [email protected] | github.com | |
| github.com/tinacms/tinacms/blob/%40tinacms/mdx%400.60.3/packages/%40tina... | [email protected] | github.com | |
| github.com/tinacms/tinacms/pull/7958 | [email protected] | github.com | |
| github.com/tinacms/tinacms/releases/tag/%40tinacms/mdx%402.4.2 | [email protected] | github.com | |
| www.vulncheck.com/advisories/tinacms-mdx-before-2.4.2-code-injection-via-mdx-se... | [email protected] | www.vulncheck.com | |
| github.com/tinacms/tinacms/security/advisories/GHSA-6vw5-w22x-ghxv | [email protected] | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Zachariah Mithani (AploSec) (en)
There are currently no legacy QID mappings associated with this CVE.