CVE-2020-5318 [High] | Security Vulnerability in Emc Isilon Onefs

Dell EMC Isilon OneFS versions 8.1.2, 8.1.0.4, 8.1.0.3, and 8.0.0.7 contain a vulnerability in some configurations. An attacker may exploit this vulnerability to gain access to restricted files. The non-RAN HTTP and WebDAV file-serving components have a vulnerability wherein when either are enabled, and Basic Authentication is enabled for either or both components, files are accessible without authentication.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	0.25%	1.13%	+0.87%
2	2025-03-30	0.49%	0.25%	-0.24%
3	2025-03-29	—	0.49%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

0.25%

1.13%

+0.87%

2025-03-30

0.49%

0.25%

-0.24%

2025-03-29

—

0.49%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
7.5	3.1	HIGH	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:N) No account or special rights needed—anonymous or random user is enough. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:N) Service keeps running; no real outage angle.	3.9	3.6	[email protected]
7.5	3.1	HIGH	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:N) No account or special rights needed—anonymous or random user is enough. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:N) Service keeps running; no real outage angle.	3.9	3.6	[email protected]
5.0	2.0	MEDIUM	`AV:N/AC:L/Au:N/C:P/I:N/A:N` Click to expand Access vector (AV:N) Can be exploited remotely over network reachability. Access complexity (AC:L) Exploitation conditions are straightforward and predictable. Authentication (AU:N) No authentication is required. Confidentiality impact (C:P) Partial confidentiality impact. Integrity impact (I:N) No integrity impact. Availability impact (A:N) No availability impact.	10.0	2.9	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

7.5

3.1

HIGH

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

Attack vector (AV:N): Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N): No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:N): Data isn’t meaningfully altered or forged.
Availability (A:N): Service keeps running; no real outage angle.

3.9

3.6

[email protected]

7.5

3.1

HIGH

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

Attack vector (AV:N): Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N): No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:N): Data isn’t meaningfully altered or forged.
Availability (A:N): Service keeps running; no real outage angle.

3.9

3.6

[email protected]

5.0

2.0

MEDIUM

AV:N/AC:L/Au:N/C:P/I:N/A:N Click to expand

Access vector (AV:N): Can be exploited remotely over network reachability.
Access complexity (AC:L): Exploitation conditions are straightforward and predictable.
Authentication (AU:N): No authentication is required.
Confidentiality impact (C:P): Partial confidentiality impact.
Integrity impact (I:N): No integrity impact.
Availability impact (A:N): No availability impact.

10.0

2.9

[email protected]

Affected software / configurations for CVE-2020-5318

Vendor	Product	Version	Raw CPE
dell	emc_isilon_onefs	8.0.0.7	cpe:2.3:a:dell:emc_isilon_onefs:8.0.0.7:::::::*
dell	emc_isilon_onefs	8.1.0.3	cpe:2.3:a:dell:emc_isilon_onefs:8.1.0.3:::::::*
dell	emc_isilon_onefs	8.1.0.4	cpe:2.3:a:dell:emc_isilon_onefs:8.1.0.4:::::::*
dell	emc_isilon_onefs	8.1.2	cpe:2.3:a:dell:emc_isilon_onefs:8.1.2:::::::*

References for CVE-2020-5318

URL	Tags
https://www.dell.com/support/security/en-us/details/540708/DSA-2020-018-Dell-EMC-Isilon-OneFS-Security-Update-for-Improper-Authorization-Vulnerability	Vendor Advisory

URL

CVE-2020-5318

Exploit prediction scoring system (EPSS) score for CVE-2020-5318

Common vulnerability scoring system (CVSS) metrics for CVE-2020-5318

Weakness enumeration for CVE-2020-5318

Affected software / configurations for CVE-2020-5318

References for CVE-2020-5318