Read the docs
TI-2023-06896 Aliases CVE-2023-20190GHSA-j3jp-5cvm-4wvf

Access control flaw in Cisco IOS XR Software

Priority LOW 27CWE-264Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
None · Low · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-264.

Summary

A vulnerability in the classic access control list (ACL) compression feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to bypass the protection that is offered by a configured ACL on an affected device. This vulnerability is due to incorrect destination address range encoding in the compression module of an ACL that is applied to an interface of an affected device. An attacker could exploit this vulnerability by sending traffic through the affected device that should be denied by the configured ACL. A successful exploit could allow the attacker to bypass configured ACL protections on the affected device, allowing the attacker to access trusted networks that the device might be protecting. 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 .

Why it matters now

EPSS 0.00712 53rd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
CiscoCisco IOS XR Software5.2.0; 5.2.1; 5.2.2; 5.2.4; 5.2.3; 5.2.5; 5.2.47; 5.3.0; 5.3.1; 5.3.2; 5.3.3; 5.3.4; 6.0.0; 6.0.1; 6.0.2; 6.1.1; 6.1.2; 6.1.3; 6.1.4; 6.1.12; 6.1.22; 6.1.32; 6.1.36; 6.1.42; 6.2.1; 6.2.2; 6.2.3; 6.2.25; 6.2.11; 6.3.2; 6.3.3; 6.3.15; 6.4.1; 6.4.2; 6.4.3; 6.5.1; 6.5.2; 6.5.3; 6.5.25; 6.5.26; 6.5.28; 6.5.29; 6.5.32; 6.5.33; 6.6.2; 6.6.3; 6.6.25; 6.6.4; 7.0.1; 7.0.2; 7.0.12; 7.0.14; 7.1.1; 7.1.15; 7.1.2; 7.1.3; 6.7.1; 6.7.2; 6.7.3; 6.7.4; 7.2.0; 7.2.1; 7.2.2; 7.3.1; 7.3.15; 7.3.2; 7.3.3; 7.4.1; 7.4.2; 6.8.1; 6.8.2; 7.5.1; 7.5.3; 7.5.2; 7.6.1; 7.6.2; 7.7.1; 7.7.2; 6.9.1; 6.9.2; 7.8.1—No fix listedCNA
  • Cisco IOS XR Software VendorCisco Affected 5.2.0; 5.2.1; 5.2.2; 5.2.4; 5.2.3; 5.2.5; 5.2.47; 5.3.0; 5.3.1; 5.3.2; 5.3.3; 5.3.4; 6.0.0; 6.0.1; 6.0.2; 6.1.1; 6.1.2; 6.1.3; 6.1.4; 6.1.12; 6.1.22; 6.1.32; 6.1.36; 6.1.42; 6.2.1; 6.2.2; 6.2.3; 6.2.25; 6.2.11; 6.3.2; 6.3.3; 6.3.15; 6.4.1; 6.4.2; 6.4.3; 6.5.1; 6.5.2; 6.5.3; 6.5.25; 6.5.26; 6.5.28; 6.5.29; 6.5.32; 6.5.33; 6.6.2; 6.6.3; 6.6.25; 6.6.4; 7.0.1; 7.0.2; 7.0.12; 7.0.14; 7.1.1; 7.1.15; 7.1.2; 7.1.3; 6.7.1; 6.7.2; 6.7.3; 6.7.4; 7.2.0; 7.2.1; 7.2.2; 7.3.1; 7.3.15; 7.3.2; 7.3.3; 7.4.1; 7.4.2; 6.8.1; 6.8.2; 7.5.1; 7.5.3; 7.5.2; 7.6.1; 7.6.2; 7.7.1; 7.7.2; 6.9.1; 6.9.2; 7.8.1 Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*before 7.3.5; 7.5 to before 7.5.4; 7.6 to before 7.8.2VulnerableCisco
cpe:2.3:o:cisco:ios_xr:7.9:*:*:*:*:*:*:*7.9VulnerableCisco
  • cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:* Versions before 7.3.5; 7.5 to before 7.5.4; 7.6 to before 7.8.2 Vulnerable ·Cisco
  • cpe:2.3:o:cisco:ios_xr:7.9:*:*:*:*:*:*:* Versions 7.9 Vulnerable ·Cisco

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-20190
  2. 2026-10-03 Alias added: GHSA-j3jp-5cvm-4wvf

References

Exploit 1

  • TI-2020-02680 Cisco IOS XR Software Cisco Discovery Protocol Format String Vulnerability KEVCVSS 3.1HIGH 8.8
  • TI-2018-00135 Memory corruption in Cisco IOS, IOS XE, and IOS XR KEVCVSS 3.1HIGH 8.8
  • TI-2020-03113 Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerabilities KEVCVSS 3.1HIGH 8.6
  • TI-2020-03110 Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerability KEVCVSS 3.1HIGH 8.6
  • TI-2018-00142 Memory corruption in Cisco IOS, IOS XE, and IOS XR KEVCVSS 3.1HIGH 8.0
  • TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
See all 199 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences