Security Digest · Vulnerability record
CVE-2026-41507: Remote Code Execution (RCE) via String Literal Injection into math-codegen
math-codegen generates code from mathematical expressions.
CVSS 9.8 Critical EPSS 0.7% · p51
Should you act?
Critical and remotely reachable
No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.
- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.7%, percentile 51: FIRST’s model estimates a 0.7% chance of exploitation activity in the next 30 days, higher than 51% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes
math-codegen(npm) < 0.4.3, fixed in 0.4.3. Check your lockfile, including transitive dependencies.
What it is
math-codegen generates code from mathematical expressions. Prior to version 0.4.3, string literal content passed to cg.parse() is injected verbatim into a new Function() body without sanitization. This allows an attacker to execute arbitrary system commands when user-controlled input reaches the parser. Any application exposing a math evaluation endpoint where user input flows into cg.parse() is vulnerable to full RCE. This issue has been patched in version 0.4.3.
From the GitHub advisory
Impact
String literal content passed to cg.parse() is injected verbatim into a new Function() body without sanitization. This allows an attacker to execute arbitrary system commands when user-controlled input reaches the parser. Any application exposing a math evaluation endpoint where user input flows into cg.parse() is vulnerable to full RCE.
Patches
The vulnerability is addressed by using JSON.stringify() on string literal values in lib/node/ConstantNode.js to ensure they are treated as data rather than code. Users should upgrade to version 0.4.3 or later.
Workarounds
Weakness type: CWE-94.
Product: math-codegen (npm) · Assigned by: GitHub_M · Published: 2026-05-08
Affected and fixed versions
| Ecosystem | Package | Vulnerable | First fixed |
|---|---|---|---|
| npm | math-codegen | < 0.4.3 | 0.4.3 |
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| mauriciopoppe | math-codegen | < 0.4.3 |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_M | 3.1 | 9.8 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| GitHub | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- Attack vector: network (remotely reachable)
- Attack complexity: low
- Privileges required: none (no login)
- User interaction: none
- Scope: unchanged
CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.
Exploitation and urgency
- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none, automatable yes, technical impact total.
- FIRST EPSS (model of 2026-10-21): 0.67% probability of exploitation activity in the next 30 days; percentile 51.
Timeline
- — GitHub-reviewed advisory GHSA-p6x5-p4xf-cc4r published (critical)
- — CVE record last updated
- — CVE record published by GitHub_M
Sources and references
Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.
Vulnerability records
- GitHub Advisory GHSA-p6x5-p4xf-cc4r github.com
- CVE.org record CVE-2026-41507 cve.org
- NVD entry CVE-2026-41507 nvd.nist.gov
Other references from the CVE record and advisory
- github.com github.com
- github.com github.com
- github.com github.com
- github.com github.com