CVE.org (no NVD analysis yet)· CNA GitHub_M

CVE-2026-112950: Vitest: Windows backslash traversal bypasses the @vitest/mocker redirect allowlist fix

Noroxi assessment

Priority: Monitor (action score 23/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.45% (FIRST EPSS).
Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. Special conditions such as timing or configuration are required.
Fixed version: @vitest/mocker (npm) 4.1.12, 5.0.3.

Low priority for now. Upgrade to @vitest/mocker (npm) 4.1.12, 5.0.3 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

Vitest is a Vite-native testing framework for JavaScript and TypeScript projects. From 4.1.11 until 4.1.12 and 5.0.3, isFileLoadingAllowed and the filesystem read interpret backslashes differently on Windows in packages/mocker/src/node/interceptorPlugin.ts. When a client can reach the Vite dev server on Windows and register a redirect mock containing backslash traversal, POSIX joining preserves a Windows backslash traversal that the later filesystem read interprets as a path separator, so the client can read a file outside server.fs.allow that the Vitest process can access. This issue is fixed in versions 4.1.12 and 5.0.3.

MediumCVSS 5.9 · v3.1—No exploit Fix available

Published: Oct 20, 2026
Updated: Oct 20, 2026
EPSS: 0.4% · 39th percentile
CWE: CWE-22

Report tools

JSON

Action score

Monitor

Low priority for now.

CVSS: 23 / 40 · 5.9 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.4%

CNA vs NVD score

NVD: —
CNA · GitHub_M: 5.9; NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

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Not in KEV: no record of exploitation in the wild
No public exploit code on record
A fix has been released

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

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Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

@vitest mocker
- >= 4.1.11, < 4.1.12, >= 5.0.0-rc.2, < 5.0.3affected
vitest-dev vitest
- >= 4.1.11, < 4.1.12, >= 5.0.0-rc.2, < 5.0.3affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Ecosystem	Package	Affected range	Fix
npm	@vitest/mocker	from 4.1.11 · before 4.1.12	4.1.12
npm	@vitest/mocker	from 5.0.0-rc.2 · before 5.0.3	5.0.3

Same product

vitest-dev: all records

Other highest-scoring records for the same primary product.

CVE-2026-53633Vitest: Exposed Browser Mode API Can Proxy CDP and Overwrite Config Files, Leading to RCE
39Monitor
CVE-2026-47428Vitest browser mode serves unsanitized otelCarrier query parameter as inline script
38Monitor
CVE-2026-73653Vitest: Browser Mode provider commands bypass the file-access permission gate
37Monitor

Published before and after this one in the same product

← EarlierCVE-2026-84373Sep 1, 2026 · Vitest: Path Traversal / Arbitrary File Read via @vitest/mocker Redirect Mock
23Monitor
← EarlierCVE-2026-112948Oct 20, 2026 · Vitest: Servers misapply `server.fs.deny`, serving `.env`, private keys, `.git`, and the API token file
26Monitor
← EarlierCVE-2026-112949Oct 20, 2026 · Vitest: Code injection via unauthenticated manual mock registration
18Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
npm:@vitest/mocker	4.1.12	Package registry (OSV)
npm:@vitest/mocker	5.0.3	Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

PublishedOct 20, 2026
Fix recordedOct 22, 2026+1 d
TodayOct 26, 2026+6 d

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

CVE-2026-7365368 days apartVitest: Browser Mode provider commands bypass the file-access permission gate
37Monitor
CVE-2026-8437349 days apartVitest: Path Traversal / Arbitrary File Read via @vitest/mocker Redirect Mock
23Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

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Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

Anyone who can reach it over the internet can trigger it.
No account or password is required.
No user action is required.
Special conditions such as timing or configuration are required.

If successful

Confidentiality: high · data can be read
Integrity: none
Availability: none

Attack vector: Network
Attack complexity: High
Privileges required: None
User interaction: None
Scope: Unchanged
Confidentiality impact: High
Integrity impact: None
Availability impact: None

Weakness class (CWE)

CWE-22 · Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

nvd-secondary

Root cause

A user-supplied file name is joined with the allowed directory, but the result is never checked to confirm it is still inside that directory.

The bug in code

The whole CWE-22 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1const file = path.join(ROOT, req.query.name);
2res.sendFile(file);

Fixed

1const file = path.resolve(ROOT, req.query.name);
2if (!file.startsWith(ROOT + path.sep)) {
3  return res.sendStatus(400);
4}
5res.sendFile(file);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Attack patterns (CAPEC)

ATT&CK techniques

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Change log

Fix✗ → ✓Oct 22, 2026, 3:36 AM UTC
Exploit maturity— → noneOct 20, 2026, 5:07 PM UTC

For records you follow, these changes also arrive as notifications. →

References

github.com/vitest-dev/vitest/commit/15cc006aa9f8683dc5f7e895d011fa7dc751ce35

Show all references (4 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records