CVE-2023-20191

highpriority · track · 30OT risk · elevatedEPSS 0.006 · 48 %ileDEEURUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.60% (48th) EPSS
CVSS 7.5 · high
Is it mine?
38 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · fstec_bdu · cisco_csaf

EPSS · scored 2026-10-28

A vulnerability in the access control list (ACL) processing on MPLS interfaces in the ingress direction of Cisco IOS XR Software could allow an unauthenticated, remote attacker to bypass a configured ACL. This vulnerability is due to incomplete support for this feature. An attacker could exploit this vulnerability by attempting to send traffic through an affected device. A successful exploit could allow the attacker to bypass an ACL on the affected device. There are workarounds that address this vulnerability. This advisory is part of the September 2023 release of the Cisco IOS XR Software Security Advisory Bundled Publication. For a complete list of the advisories and links to them, see Cisco Event Response: September 2023 Semiannual Cisco IOS XR Software Security Advisory Bundled Publication .

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

02

cvss

Technical severity, 0–10. One row per scoring source.

7.5
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.8–7.5

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 3.6
v3.15.8mediumAV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:Nsecondary · FSTEC (BDU) RU
v3.15.8mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:Nsecondary · ENISA EU
v3.15.8mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:Nsecondary · psirt@cisco.com USexploitability 3.9 · impact 1.4
v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)
v3.15.8mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:Nsecondary · Cisco PSIRT US
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-863USprimaryCWE-264USCWE-284USCWE-284US
04

affected products (38)

Products and version ranges known to be affected.

showing 20 of 38
05

advisories (2)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2023-2355Cisco IOS XR: Mehrere SchwachstellenDeutsch2023-09-13csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in Cisco IOS XR ausnutzen, um beliebigen Code auszuführen, Sicherheitsmaßnahmen zu umgehen oder einen Denial-of-Service-Zustand zu verursachen.

  • cisco-sa-dnx-acl-PyzDkeYFCisco IOS XR Software Access Control List Bypass Vulnerability2023-09-13csaf · cisco_csafUS

    A vulnerability in the access control list (ACL) processing on MPLS interfaces in the ingress direction of Cisco IOS XR Software could allow an unauthenticated, remote attacker to bypass a configured ACL. This vulnerability is due to incomplete support for this feature. An attacker could exploit this vulnerability by attempting to send traffic through an affected device. A successful exploit could allow the attacker to bypass an ACL on the affected device. Cisco has released software updates that address this vulnerability. There are workarounds that address this vulnerability. This advisory is part of the September 2023 release of the Cisco IOS XR Software Security Advisory Bundled Publication. For a complete list of the advisories and links to them, see Cisco Event Response: September 2023 Semiannual Cisco IOS XR Software Security Advisory Bundled Publication ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-75241"].

06

also known as (4)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducisco_csafcert_bundNVDCVE.orgMITRE
published 2023-09-13modified 2026-06-17
09

references (5)

External citations — patches, advisories, analysis.

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