CVE-2023-20049
No exploitation reported by the sources we read.
- Published2023-03-09
- Fixed in7.6.2 · 7.5.3
- WeaknessCWE-119 · CWE-805
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
Description
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.
Timeline
dates in UTC- 2023-03-0922:15CVE publishedNVD
Observed activity
isMalicious corpus · updated 2026-10-23 21:37 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2023-20049?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2023-20049?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 7.6 | ≥ 7.6, < 7.6.2 | 7.6.2 | NVD |
| 7.5 | < 7.5.3 | 7.5.3 | NVD |
| 7.7 | = 7.7 | no fix published | NVD |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Fix
- Update Cisco ios xr to 7.6.2 · 7.5.3
Advisories and patches
- sec.cloudapps.cisco.comVendor Advisory
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
Sources
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Published
- 2023-03-09
- Last Modified
- 2026-06-17
- NVD status
- Modified
Frequently asked questions
What is CVE-2023-20049?
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Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.