Cisco IOS XR Software Internet Key Exchange Version 2 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-770.
Summary
A vulnerability in the Internet Key Exchange version 2 (IKEv2) function of Cisco IOS XR Software could allow an unauthenticated, remote attacker to prevent an affected device from processing any control plane UDP packets. This vulnerability is due to improper handling of malformed IKEv2 packets. An attacker could exploit this vulnerability by sending malformed IKEv2 packets to an affected device. A successful exploit could allow the attacker to prevent the affected device from processing any control plane UDP packets, resulting in a denial of service (DoS) condition. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.
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 | 6.5.3; 6.6.1; 6.5.2; 6.6.2; 6.5.1; 7.0.1; 6.6.25; 7.0.0; 7.1.1; 6.6.3; 7.0.2; 7.2.0; 7.1.2; 7.2.1; 7.3.1; 7.4.1; 7.2.2; 7.3.2; 7.5.1; 7.3.27; 7.6.1; 7.5.2; 7.7.1; 7.4.2; 7.6.2; 7.8.1; 7.7.2; 7.9.1; 7.8.2; 7.8.22; 7.10.1; 7.7.21; 7.9.2; 7.11.1; 7.10.2; 24.1.1; 7.11.2; 24.2.1; 24.1.2; 24.2.11 | — | No fix listed | CNA |
- Cisco IOS XR Software VendorCisco Affected 6.5.3; 6.6.1; 6.5.2; 6.6.2; 6.5.1; 7.0.1; 6.6.25; 7.0.0; 7.1.1; 6.6.3; 7.0.2; 7.2.0; 7.1.2; 7.2.1; 7.3.1; 7.4.1; 7.2.2; 7.3.2; 7.5.1; 7.3.27; 7.6.1; 7.5.2; 7.7.1; 7.4.2; 7.6.2; 7.8.1; 7.7.2; 7.9.1; 7.8.2; 7.8.22; 7.10.1; 7.7.21; 7.9.2; 7.11.1; 7.10.2; 24.1.1; 7.11.2; 24.2.1; 24.1.2; 24.2.11 Fixed in — No fix listed CNA
CPE configurations NVD · 44
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:cisco:ios_xr:6.5.1:*:*:*:*:*:*:* | 6.5.1 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:6.5.2:*:*:*:*:*:*:* | 6.5.2 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:6.5.3:*:*:*:*:*:*:* | 6.5.3 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:6.6.1:*:*:*:*:*:*:* | 6.6.1 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:6.6.2:*:*:*:*:*:*:* | 6.6.2 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:6.6.3:*:*:*:*:*:*:* | 6.6.3 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:6.6.25:*:*:*:*:*:*:* | 6.6.25 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.0.0:*:*:*:*:*:*:* | 7.0.0 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.0.1:*:*:*:*:*:*:* | 7.0.1 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.0.2:*:*:*:*:*:*:* | 7.0.2 | Vulnerable | Cisco |
- cpe:2.3:o:cisco:ios_xr:6.5.1:*:*:*:*:*:*:* Versions 6.5.1 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:6.5.2:*:*:*:*:*:*:* Versions 6.5.2 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:6.5.3:*:*:*:*:*:*:* Versions 6.5.3 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:6.6.1:*:*:*:*:*:*:* Versions 6.6.1 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:6.6.2:*:*:*:*:*:*:* Versions 6.6.2 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:6.6.3:*:*:*:*:*:*:* Versions 6.6.3 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:6.6.25:*:*:*:*:*:*:* Versions 6.6.25 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.0.0:*:*:*:*:*:*:* Versions 7.0.0 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.0.1:*:*:*:*:*:*:* Versions 7.0.1 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.0.2:*:*:*:*:*:*:* Versions 7.0.2 Vulnerable ·Cisco
Show 34 more CPE
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:cisco:ios_xr:7.1.1:*:*:*:*:*:*:* | 7.1.1 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.1.2:*:*:*:*:*:*:* | 7.1.2 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.2.0:*:*:*:*:*:*:* | 7.2.0 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.2.1:*:*:*:*:*:*:* | 7.2.1 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.2.2:*:*:*:*:*:*:* | 7.2.2 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.3.1:*:*:*:*:*:*:* | 7.3.1 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.3.2:*:*:*:*:*:*:* | 7.3.2 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.3.27:*:*:*:*:*:*:* | 7.3.27 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.4.1:*:*:*:*:*:*:* | 7.4.1 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.4.2:*:*:*:*:*:*:* | 7.4.2 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.5.1:*:*:*:*:*:*:* | 7.5.1 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.5.2:*:*:*:*:*:*:* | 7.5.2 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.6.1:*:*:*:*:*:*:* | 7.6.1 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.6.2:*:*:*:*:*:*:* | 7.6.2 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.7.1:*:*:*:*:*:*:* | 7.7.1 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.7.2:*:*:*:*:*:*:* | 7.7.2 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.7.21:*:*:*:*:*:*:* | 7.7.21 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.8.1:*:*:*:*:*:*:* | 7.8.1 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.8.2:*:*:*:*:*:*:* | 7.8.2 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.8.22:*:*:*:*:*:*:* | 7.8.22 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.9.1:*:*:*:*:*:*:* | 7.9.1 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.9.2:*:*:*:*:*:*:* | 7.9.2 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.10.1:*:*:*:*:*:*:* | 7.10.1 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.10.2:*:*:*:*:*:*:* | 7.10.2 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.11.1:*:*:*:*:*:*:* | 7.11.1 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:7.11.2:*:*:*:*:*:*:* | 7.11.2 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:24.1.1:*:*:*:*:*:*:* | 24.1.1 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:24.1.2:*:*:*:*:*:*:* | 24.1.2 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:24.2.1:*:*:*:*:*:*:* | 24.2.1 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xr:24.2.11:*:*:*:*:*:*:* | 24.2.11 | Vulnerable | Cisco |
| cpe:2.3:h:cisco:ncs_1004:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:ncs_1010:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:ncs_1014:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:ncs_540l:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
- cpe:2.3:o:cisco:ios_xr:7.1.1:*:*:*:*:*:*:* Versions 7.1.1 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.1.2:*:*:*:*:*:*:* Versions 7.1.2 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.2.0:*:*:*:*:*:*:* Versions 7.2.0 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.2.1:*:*:*:*:*:*:* Versions 7.2.1 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.2.2:*:*:*:*:*:*:* Versions 7.2.2 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.3.1:*:*:*:*:*:*:* Versions 7.3.1 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.3.2:*:*:*:*:*:*:* Versions 7.3.2 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.3.27:*:*:*:*:*:*:* Versions 7.3.27 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.4.1:*:*:*:*:*:*:* Versions 7.4.1 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.4.2:*:*:*:*:*:*:* Versions 7.4.2 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.5.1:*:*:*:*:*:*:* Versions 7.5.1 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.5.2:*:*:*:*:*:*:* Versions 7.5.2 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.6.1:*:*:*:*:*:*:* Versions 7.6.1 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.6.2:*:*:*:*:*:*:* Versions 7.6.2 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.7.1:*:*:*:*:*:*:* Versions 7.7.1 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.7.2:*:*:*:*:*:*:* Versions 7.7.2 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.7.21:*:*:*:*:*:*:* Versions 7.7.21 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.8.1:*:*:*:*:*:*:* Versions 7.8.1 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.8.2:*:*:*:*:*:*:* Versions 7.8.2 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.8.22:*:*:*:*:*:*:* Versions 7.8.22 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.9.1:*:*:*:*:*:*:* Versions 7.9.1 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.9.2:*:*:*:*:*:*:* Versions 7.9.2 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.10.1:*:*:*:*:*:*:* Versions 7.10.1 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.10.2:*:*:*:*:*:*:* Versions 7.10.2 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.11.1:*:*:*:*:*:*:* Versions 7.11.1 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:7.11.2:*:*:*:*:*:*:* Versions 7.11.2 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:24.1.1:*:*:*:*:*:*:* Versions 24.1.1 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:24.1.2:*:*:*:*:*:*:* Versions 24.1.2 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:24.2.1:*:*:*:*:*:*:* Versions 24.2.1 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xr:24.2.11:*:*:*:*:*:*:* Versions 24.2.11 Vulnerable ·Cisco
- cpe:2.3:h:cisco:ncs_1004:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:ncs_1010:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:ncs_1014:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:ncs_540l:-:*:*:*:*:*:*:* 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-2025-20209
- 2026-10-03 Alias added: GHSA-f769-hvjj-2wv2
References
Advisory 1
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-2025-20209 · CVE Program
- CVE-2025-20209 · NVD
- FIRST EPSS
- GHSA-f769-hvjj-2wv2 · 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