NVD / CVE Program· CNA mitre

CVE-2020-28187: Multiple directory traversal vulnerabilities in TerraMaster TOS <= 4.2.06 allow remote authenticated attackers to read, edit or delete any f

Noroxi assessment

Priority: Plan (action score 44/100)

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: 16.3% (FIRST EPSS); higher than 96.9% of all records.
Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
According to the record, no fixed version is available yet.

Add it to your regular patch cycle. Update when a fix is released; follow the vendor's advisory.

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

Multiple directory traversal vulnerabilities in TerraMaster TOS <= 4.2.06 allow remote authenticated attackers to read, edit or delete any file within the filesystem via the (1) filename parameter to /tos/index.php?editor/fileGet, Event parameter to /include/ajax/logtable.php, or opt parameter to /include/core/index.php.

CriticalCVSS 9.8 · v3.1—No exploit No fix recorded

Published: Dec 24, 2020
Updated: Jun 16, 2026
EPSS: 16.3% · 96th percentile
CWE: CWE-22

Report tools

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Action score

Plan

Add it to your regular patch cycle.

CVSS: 39 / 40 · 9.8 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 5 / 30 · 16.3%

Get told when this record changes

Not in KEV: no record of exploitation in the wild
No public exploit code on record
No fixed version yet

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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.

Vendor	Product	CPE
terra-master	tos	cpe:2.3:o:terra-master:tos

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

terra-master tosup to 4.2.06 inclusive

Same product

terra-master: all records

Other highest-scoring records for the same primary product.

CVE-2020-28188Remote Command Execution (RCE) vulnerability in TerraMaster TOS <= 4.2.06 allow remote unauthenticated attackers to inject OS commands via /
68This week
CVE-2021-45841In Terramaster F4-210, F2-210 TOS 4.2.X (4.2.15-2107141517), an attacker can self-sign session cookies by knowing the target's MAC address a
60This week
CVE-2021-45837It is possible to execute arbitrary commands as root in Terramaster F4-210, F2-210 TOS 4.2.X (4.2.15-2107141517) by sending a specifically c
60This week

Published before and after this one in the same product

← EarlierCVE-2020-28185Dec 24, 2020 · User Enumeration vulnerability in TerraMaster TOS <= 4.2.06 allows remote unauthenticated attackers to identify valid users within the syste
26Monitor
← EarlierCVE-2020-28186Dec 24, 2020 · Email Injection in TerraMaster TOS <= 4.2.06 allows remote unauthenticated attackers to abuse the forget password functionality and achieve
30Monitor
Later →CVE-2020-28190Dec 24, 2020 · TerraMaster TOS <= 4.2.06 was found to check for updates (of both system and applications) via an insecure channel (HTTP).
23Monitor

Remediation

Which version to upgrade to

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

No fix version is recorded for this entry. Check the references for vendor advisories.

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.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

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

No commit or PR link among the references.

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.

No nightly-computed relations.

Chain candidates

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

—

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.
No special conditions are required; it is repeatable.

If successful

Confidentiality: high · data can be read
Integrity: high · data or configuration can be modified
Availability: high · the service can be disrupted

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

Weakness class (CWE)

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

CVSS vector

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

nvd-primary

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

No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.

References

www.terra-master.com/

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

All records