CVE-2023-20187
A vulnerability in the Multicast Leaf Recycle Elimination (mLRE) feature of Cisco IOS XE Software for Cisco ASR 1000 Series Aggregation…
- 8.6HighCVSS base score
- 0.88%Exploitation in 30 daysEPSS · top 41% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
A vulnerability in the Multicast Leaf Recycle Elimination (mLRE) feature of Cisco IOS XE Software for Cisco ASR 1000 Series Aggregation Services Routers could allow an unauthenticated, remote attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition. This vulnerability is due to incorrect handling of certain IPv6 multicast packets when they are fanned out more than seven times on an affected device. An attacker could exploit this vulnerability by sending a specific IPv6 multicast or IPv6 multicast VPN (MVPNv6) packet through the affected device. A successful exploit could allow the attacker to cause a reload of the affected device, resulting in a DoS condition.
Timeline
ID reserved
By cisco
- 11 months later
· 11 months later
Published
- 10 months later
· 10 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| ciscoCNA (assigner) | 3.1 | High8.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H |
| NVDNVD · Modified | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.88% · top 41% of all CVEs (11 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.6.
Affected products
- affected 3.7.1S
- affected 3.7.2S
- affected 3.7.3S
- affected 3.7.4S
- affected 3.7.5S
- affected 3.7.6S
- affected 3.7.7S
- affected 3.7.2tS
- affected 3.8.0S
- affected 3.8.1S
- affected 3.8.2S
- affected 3.9.1S
- affected 3.9.0S
- affected 3.9.2S
- affected 3.10.0S
- affected 3.10.1S
- affected 3.10.2S
- affected 3.10.3S
- affected 3.10.4S
- affected 3.10.5S
- affected 3.10.6S
- affected 3.10.7S
- affected 3.10.1xbS
- affected 3.10.8S
- affected 3.10.8aS
- affected 3.10.9S
- affected 3.10.10S
- affected 3.11.1S
- affected 3.11.2S
- affected 3.11.0S
- affected 3.11.3S
- affected 3.11.4S
- affected 3.12.0S
- affected 3.12.1S
- affected 3.12.2S
- affected 3.12.3S
- affected 3.12.4S
- affected 3.13.0S
- affected 3.13.1S
- affected 3.13.2S
- and 163 more
What to do
Exploitation: The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.
References
References1
- cisco-sa-mlre-H93FswRz (opens in a new tab)x_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2023-24366 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2023-20187)Record last updated .