CVE-2026-20263Cisco IOS XE Software Blocks Extensible Exchange Protocol Denial of Service Vulnerability
- 8.6HighCVSS base score
- 0.57%Exploitation in 30 daysEPSS · top 52% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
A vulnerability in the Blocks Extensible Exchange Protocol (BEEP) feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper handling when parsing a specific BEEP SOAP request. An attacker could exploit this vulnerability by sending a specific BEEP SOAP request to an affected device. A successful exploit could allow the attacker to cause the device to reload unexpectedly, resulting in a DoS condition.
Timeline
ID reserved
By cisco
- 10 months later
· 10 months later
Published
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 · Analyzed | 3.1 | High8.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.57% · top 52% of all CVEs (14 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.6.
Affected products
- affected 17.2.1a
- affected 16.12.1y
- affected 16.12.3s
- affected 16.7.1b
- affected 16.6.2
- affected 16.6.5
- affected 16.12.1w
- affected 16.9.1d
- affected 17.3.1
- affected 16.9.4c
- affected 16.7.1
- affected 17.2.1
- affected 16.6.8
- affected 16.9.1b
- affected 16.9.2s
- affected 16.12.4
- affected 16.12.3a
- affected 17.1.1s
- affected 16.11.1a
- affected 16.7.2
- affected 16.11.1b
- affected 16.9.1s
- affected 16.9.3h
- affected 16.9.1c
- affected 16.6.5a
- affected 16.6.3
- affected 16.10.1f
- affected 17.2.1v
- affected 16.8.1e
- affected 16.9.3a
- affected 16.12.1a
- affected 16.12.1x
- affected 16.6.4s
- affected 16.10.1c
- affected 16.12.3
- affected 16.11.2
- affected 16.6.5b
- affected 16.12.2s
- affected 16.10.1b
- affected 16.7.3
- and 227 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
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-2026-53452 (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-2026-20263)Record last updated .