Cisco IOS XR Software for ASR 9000 Series Routers Bidirectional Forwarding Detection Denial of Service Vulnerability
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-119 and the CVSS impact.
Summary
A vulnerability in the bidirectional forwarding detection (BFD) hardware offload feature of Cisco IOS XR Software for Cisco ASR 9000 Series Aggregation Services Routers, ASR 9902 Compact High-Performance Routers, and ASR 9903 Compact High-Performance Routers could allow an unauthenticated, remote attacker to cause a line card to reset, resulting in a denial of service (DoS) condition. This vulnerability is due to the incorrect handling of malformed BFD packets that are received on line cards where the BFD hardware offload feature is enabled. An attacker could exploit this vulnerability by sending a crafted IPv4 BFD packet to an affected device. A successful exploit could allow the attacker to cause line card exceptions or a hard reset, resulting in loss of traffic over that line card while the line card reloads.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Cisco | Cisco IOS XR Software | all versions | — | No fix listed | CNA |
- Cisco IOS XR Software VendorCisco Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 14
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:* | before 7.5.3; 7.6 to before 7.6.2 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.7:*:*:*:*:*:*:* | 7.7 | Vulnerable | Cisco |
| cpe:2.3:h:cisco:asr_9000v-v2:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:asr_9001:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:asr_9006:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:asr_9010:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:asr_9901:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:asr_9902:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:asr_9903:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:asr_9904:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
- cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:* Versions before 7.5.3; 7.6 to before 7.6.2 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.7:*:*:*:*:*:*:* Versions 7.7 Vulnerable ·Cisco
- cpe:2.3:h:cisco:asr_9000v-v2:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:asr_9001:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:asr_9006:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:asr_9010:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:asr_9901:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:asr_9902:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:asr_9903:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:asr_9904:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
Show 4 more CPE
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:h:cisco:asr_9906:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:asr_9910:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:asr_9912:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:asr_9922:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
- cpe:2.3:h:cisco:asr_9906:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:asr_9910:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:asr_9912:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:asr_9922:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2023-20049
- 2026-10-03 Alias added: GHSA-3q76-jpjg-96ff
References
More Cisco Ios Xr vulnerabilities
- 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
Sources
- CVE-2023-20049 · CVE Program
- CVE-2023-20049 · NVD
- FIRST EPSS
- GHSA-3q76-jpjg-96ff · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences