CVE-2023-20185 [High] | Security Vulnerability in Nx-Os

A vulnerability in the Cisco ACI Multi-Site CloudSec encryption feature of Cisco Nexus 9000 Series Fabric Switches in ACI mode could allow an unauthenticated, remote attacker to read or modify intersite encrypted traffic. This vulnerability is due to an issue with the implementation of the ciphers that are used by the CloudSec encryption feature on affected switches. An attacker with an on-path position between the ACI sites could exploit this vulnerability by intercepting intersite encrypted traffic and using cryptanalytic techniques to break the encryption. A successful exploit could allow the attacker to read or modify the traffic that is transmitted between the sites. Cisco has not released and will not release software updates that address this vulnerability.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-04-06	0.08%	0.17%	+0.10%
2	2023-07-14	0.05%	0.08%	+0.03%
3	2023-07-13	—	0.05%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-04-06

0.08%

0.17%

+0.10%

2023-07-14

0.05%

0.08%

+0.03%

2023-07-13

—

0.05%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
7.4	3.1	HIGH	`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/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:H) Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work. 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:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:N) Service keeps running; no real outage angle.	2.2	5.2	[email protected]
7.4	3.1	HIGH	`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/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:H) Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work. 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:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:N) Service keeps running; no real outage angle.	2.2	5.2	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

7.4

3.1

HIGH

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/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:H): Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
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:H): They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N): Service keeps running; no real outage angle.

2.2

5.2

[email protected]

7.4

3.1

HIGH

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/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:H): Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
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:H): They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N): Service keeps running; no real outage angle.

2.2

5.2

[email protected]

Affected software / configurations for CVE-2023-20185

Vendor	Product	Version	Raw CPE
cisco	nx-os	14.0\(1h\)	cpe:2.3:o:cisco:nx-os:14.0\(1h\):::::::*
cisco	nx-os	14.0\(2c\)	cpe:2.3:o:cisco:nx-os:14.0\(2c\):::::::*
cisco	nx-os	14.0\(3c\)	cpe:2.3:o:cisco:nx-os:14.0\(3c\):::::::*
cisco	nx-os	14.0\(3d\)	cpe:2.3:o:cisco:nx-os:14.0\(3d\):::::::*
cisco	nx-os	14.1\(1i\)	cpe:2.3:o:cisco:nx-os:14.1\(1i\):::::::*
cisco	nx-os	14.1\(1j\)	cpe:2.3:o:cisco:nx-os:14.1\(1j\):::::::*
cisco	nx-os	14.1\(1k\)	cpe:2.3:o:cisco:nx-os:14.1\(1k\):::::::*
cisco	nx-os	14.1\(1l\)	cpe:2.3:o:cisco:nx-os:14.1\(1l\):::::::*
cisco	nx-os	14.1\(2g\)	cpe:2.3:o:cisco:nx-os:14.1\(2g\):::::::*
cisco	nx-os	14.1\(2m\)	cpe:2.3:o:cisco:nx-os:14.1\(2m\):::::::*
cisco	nx-os	14.1\(2o\)	cpe:2.3:o:cisco:nx-os:14.1\(2o\):::::::*
cisco	nx-os	14.1\(2s\)	cpe:2.3:o:cisco:nx-os:14.1\(2s\):::::::*
cisco	nx-os	14.1\(2u\)	cpe:2.3:o:cisco:nx-os:14.1\(2u\):::::::*
cisco	nx-os	14.1\(2w\)	cpe:2.3:o:cisco:nx-os:14.1\(2w\):::::::*
cisco	nx-os	14.1\(2x\)	cpe:2.3:o:cisco:nx-os:14.1\(2x\):::::::*
cisco	nx-os	14.2\(1i\)	cpe:2.3:o:cisco:nx-os:14.2\(1i\):::::::*
cisco	nx-os	14.2\(1j\)	cpe:2.3:o:cisco:nx-os:14.2\(1j\):::::::*
cisco	nx-os	14.2\(1l\)	cpe:2.3:o:cisco:nx-os:14.2\(1l\):::::::*
cisco	nx-os	14.2\(2e\)	cpe:2.3:o:cisco:nx-os:14.2\(2e\):::::::*
cisco	nx-os	14.2\(2f\)	cpe:2.3:o:cisco:nx-os:14.2\(2f\):::::::*
cisco	nx-os	14.2\(2g\)	cpe:2.3:o:cisco:nx-os:14.2\(2g\):::::::*
cisco	nx-os	14.2\(3j\)	cpe:2.3:o:cisco:nx-os:14.2\(3j\):::::::*
cisco	nx-os	14.2\(3l\)	cpe:2.3:o:cisco:nx-os:14.2\(3l\):::::::*
cisco	nx-os	14.2\(3n\)	cpe:2.3:o:cisco:nx-os:14.2\(3n\):::::::*
cisco	nx-os	14.2\(3q\)	cpe:2.3:o:cisco:nx-os:14.2\(3q\):::::::*
cisco	nx-os	14.2\(4i\)	cpe:2.3:o:cisco:nx-os:14.2\(4i\):::::::*
cisco	nx-os	14.2\(4k\)	cpe:2.3:o:cisco:nx-os:14.2\(4k\):::::::*
cisco	nx-os	14.2\(4o\)	cpe:2.3:o:cisco:nx-os:14.2\(4o\):::::::*
cisco	nx-os	14.2\(4p\)	cpe:2.3:o:cisco:nx-os:14.2\(4p\):::::::*
cisco	nx-os	14.2\(5k\)	cpe:2.3:o:cisco:nx-os:14.2\(5k\):::::::*
cisco	nx-os	14.2\(5l\)	cpe:2.3:o:cisco:nx-os:14.2\(5l\):::::::*
cisco	nx-os	14.2\(5n\)	cpe:2.3:o:cisco:nx-os:14.2\(5n\):::::::*
cisco	nx-os	14.2\(6d\)	cpe:2.3:o:cisco:nx-os:14.2\(6d\):::::::*
cisco	nx-os	14.2\(6g\)	cpe:2.3:o:cisco:nx-os:14.2\(6g\):::::::*
cisco	nx-os	14.2\(6h\)	cpe:2.3:o:cisco:nx-os:14.2\(6h\):::::::*
cisco	nx-os	14.2\(6l\)	cpe:2.3:o:cisco:nx-os:14.2\(6l\):::::::*
cisco	nx-os	14.2\(6o\)	cpe:2.3:o:cisco:nx-os:14.2\(6o\):::::::*
cisco	nx-os	14.2\(7f\)	cpe:2.3:o:cisco:nx-os:14.2\(7f\):::::::*
cisco	nx-os	14.2\(7l\)	cpe:2.3:o:cisco:nx-os:14.2\(7l\):::::::*
cisco	nx-os	14.2\(7q\)	cpe:2.3:o:cisco:nx-os:14.2\(7q\):::::::*
cisco	nx-os	14.2\(7r\)	cpe:2.3:o:cisco:nx-os:14.2\(7r\):::::::*
cisco	nx-os	14.2\(7s\)	cpe:2.3:o:cisco:nx-os:14.2\(7s\):::::::*
cisco	nx-os	14.2\(7t\)	cpe:2.3:o:cisco:nx-os:14.2\(7t\):::::::*
cisco	nx-os	14.2\(7u\)	cpe:2.3:o:cisco:nx-os:14.2\(7u\):::::::*
cisco	nx-os	14.2\(7v\)	cpe:2.3:o:cisco:nx-os:14.2\(7v\):::::::*
cisco	nx-os	14.2\(7w\)	cpe:2.3:o:cisco:nx-os:14.2\(7w\):::::::*
cisco	nx-os	15.0\(1k\)	cpe:2.3:o:cisco:nx-os:15.0\(1k\):::::::*
cisco	nx-os	15.0\(1l\)	cpe:2.3:o:cisco:nx-os:15.0\(1l\):::::::*
cisco	nx-os	15.0\(2e\)	cpe:2.3:o:cisco:nx-os:15.0\(2e\):::::::*
cisco	nx-os	15.0\(2h\)	cpe:2.3:o:cisco:nx-os:15.0\(2h\):::::::*
cisco	nx-os	15.1\(1h\)	cpe:2.3:o:cisco:nx-os:15.1\(1h\):::::::*
cisco	nx-os	15.1\(2e\)	cpe:2.3:o:cisco:nx-os:15.1\(2e\):::::::*
cisco	nx-os	15.1\(3e\)	cpe:2.3:o:cisco:nx-os:15.1\(3e\):::::::*
cisco	nx-os	15.1\(4c\)	cpe:2.3:o:cisco:nx-os:15.1\(4c\):::::::*
cisco	nx-os	15.2\(1g\)	cpe:2.3:o:cisco:nx-os:15.2\(1g\):::::::*
cisco	nx-os	15.2\(2e\)	cpe:2.3:o:cisco:nx-os:15.2\(2e\):::::::*
cisco	nx-os	15.2\(2f\)	cpe:2.3:o:cisco:nx-os:15.2\(2f\):::::::*
cisco	nx-os	15.2\(2g\)	cpe:2.3:o:cisco:nx-os:15.2\(2g\):::::::*
cisco	nx-os	15.2\(2h\)	cpe:2.3:o:cisco:nx-os:15.2\(2h\):::::::*
cisco	nx-os	15.2\(3e\)	cpe:2.3:o:cisco:nx-os:15.2\(3e\):::::::*
cisco	nx-os	15.2\(3f\)	cpe:2.3:o:cisco:nx-os:15.2\(3f\):::::::*
cisco	nx-os	15.2\(3g\)	cpe:2.3:o:cisco:nx-os:15.2\(3g\):::::::*
cisco	nx-os	15.2\(4d\)	cpe:2.3:o:cisco:nx-os:15.2\(4d\):::::::*
cisco	nx-os	15.2\(4e\)	cpe:2.3:o:cisco:nx-os:15.2\(4e\):::::::*
cisco	nx-os	15.2\(4f\)	cpe:2.3:o:cisco:nx-os:15.2\(4f\):::::::*
cisco	nx-os	15.2\(5c\)	cpe:2.3:o:cisco:nx-os:15.2\(5c\):::::::*
cisco	nx-os	15.2\(5d\)	cpe:2.3:o:cisco:nx-os:15.2\(5d\):::::::*
cisco	nx-os	15.2\(5e\)	cpe:2.3:o:cisco:nx-os:15.2\(5e\):::::::*
cisco	nx-os	15.2\(6e\)	cpe:2.3:o:cisco:nx-os:15.2\(6e\):::::::*
cisco	nx-os	15.2\(6g\)	cpe:2.3:o:cisco:nx-os:15.2\(6g\):::::::*
cisco	nx-os	15.2\(7f\)	cpe:2.3:o:cisco:nx-os:15.2\(7f\):::::::*
cisco	nx-os	15.2\(7g\)	cpe:2.3:o:cisco:nx-os:15.2\(7g\):::::::*
cisco	nx-os	15.2\(8d\)	cpe:2.3:o:cisco:nx-os:15.2\(8d\):::::::*
cisco	nx-os	16.0\(1g\)	cpe:2.3:o:cisco:nx-os:16.0\(1g\):::::::*
cisco	nx-os	16.0\(1j\)	cpe:2.3:o:cisco:nx-os:16.0\(1j\):::::::*
cisco	nx-os	16.0\(2h\)	cpe:2.3:o:cisco:nx-os:16.0\(2h\):::::::*

References for CVE-2023-20185

URL	Tags
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-aci-cloudsec-enc-Vs5Wn2sX	Vendor Advisory

URL

CVE-2023-20185

Exploit prediction scoring system (EPSS) score for CVE-2023-20185

Common vulnerability scoring system (CVSS) metrics for CVE-2023-20185

Weakness enumeration for CVE-2023-20185

Affected software / configurations for CVE-2023-20185

References for CVE-2023-20185