CVE-2023-20226 [High] | Denial of Service in Ios Xe

A vulnerability in Application Quality of Experience (AppQoE) and Unified Threat Defense (UTD) on Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to the mishandling of a crafted packet stream through the AppQoE or UTD application. An attacker could exploit this vulnerability by sending a crafted packet stream through an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	0.18%	0.70%	+0.53%
2	2025-03-19	0.06%	0.18%	+0.11%
3	2023-10-07	—	0.06%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

0.18%

0.70%

+0.53%

2025-03-19

0.06%

0.18%

+0.11%

2023-10-07

—

0.06%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
8.6	3.1	HIGH	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H` 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:C) Breaking this can reach past the original component and bite other resources—bigger blast radius. Confidentiality (C:N) Doesn’t really leak secrets in a meaningful way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	3.9	4.0	[email protected]
7.5	3.1	HIGH	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H` 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:N) Doesn’t really leak secrets in a meaningful way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	3.9	3.6	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

8.6

3.1

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H 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:C): Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:N): Doesn’t really leak secrets in a meaningful way.
Integrity (I:N): Data isn’t meaningfully altered or forged.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

3.9

4.0

[email protected]

7.5

3.1

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H 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:N): Doesn’t really leak secrets in a meaningful way.
Integrity (I:N): Data isn’t meaningfully altered or forged.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

3.9

3.6

[email protected]

Affected software / configurations for CVE-2023-20226

Vendor	Product	Version	Raw CPE
cisco	ios_xe	17.7.1	cpe:2.3:o:cisco:ios_xe:17.7.1:::::::*
cisco	ios_xe	17.7.1a	cpe:2.3:o:cisco:ios_xe:17.7.1a:::::::*
cisco	ios_xe	17.7.2	cpe:2.3:o:cisco:ios_xe:17.7.2:::::::*
cisco	ios_xe	17.8.1	cpe:2.3:o:cisco:ios_xe:17.8.1:::::::*
cisco	ios_xe	17.8.1a	cpe:2.3:o:cisco:ios_xe:17.8.1a:::::::*
cisco	ios_xe	17.9.1	cpe:2.3:o:cisco:ios_xe:17.9.1:::::::*
cisco	ios_xe	17.9.1a	cpe:2.3:o:cisco:ios_xe:17.9.1a:::::::*
cisco	ios_xe	17.9.2	cpe:2.3:o:cisco:ios_xe:17.9.2:::::::*
cisco	ios_xe	17.9.2a	cpe:2.3:o:cisco:ios_xe:17.9.2a:::::::*
cisco	ios_xe	17.10.1	cpe:2.3:o:cisco:ios_xe:17.10.1:::::::*
cisco	ios_xe	17.10.1a	cpe:2.3:o:cisco:ios_xe:17.10.1a:::::::*

References for CVE-2023-20226

URL	Tags
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-appqoe-utd-dos-p8O57p5y	Vendor Advisory

URL

CVE-2023-20226

Exploit prediction scoring system (EPSS) score for CVE-2023-20226

Common vulnerability scoring system (CVSS) metrics for CVE-2023-20226

Weakness enumeration for CVE-2023-20226

Affected software / configurations for CVE-2023-20226

References for CVE-2023-20226