Cisco IOS XE SD-WAN Software Arbitrary File Overwrite Vulnerability
Priority LOW 31CWE-668Published · Updated
Key facts
- Attack vector
- Local
- Privileges required
- High
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA.
Summary
A vulnerability in a specific CLI command that is run on Cisco IOS XE SD-WAN Software could allow an authenticated, local attacker to overwrite arbitrary files in the configuration database of an affected device. This vulnerability is due to insufficient validation of specific CLI command parameters. An attacker could exploit this vulnerability by issuing that command with specific parameters. A successful exploit could allow the attacker to overwrite the content of the configuration database and gain root-level access to an affected device.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00245 15th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
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 XE Software | all versions | — | No fix listed | CNA |
- Cisco IOS XE Software VendorCisco Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 21
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:cisco:ios_xe:17.3.1a:*:*:*:*:*:*:* | 17.3.1a | Vulnerable | Cisco |
| cpe:2.3:h:cisco:asr_1000-x:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:asr_1001:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:asr_1001-x:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:asr_1002:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:asr_1002-x:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:asr_1004:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:asr_1006:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:asr_1013:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:asr_1023:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
- cpe:2.3:o:cisco:ios_xe:17.3.1a:*:*:*:*:*:*:* Versions 17.3.1a Vulnerable ·Cisco
- cpe:2.3:h:cisco:asr_1000-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:asr_1001:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:asr_1001-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:asr_1002:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:asr_1002-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:asr_1004:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:asr_1006:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:asr_1013:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:asr_1023:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
Show 11 more CPE
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:h:cisco:4321_integrated_services_router:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:4331_integrated_services_router:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:4351_integrated_services_router:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:4431_integrated_services_router:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:1100-4g_integrated_services_router:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:1100-4gltegb_integrated_services_router:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:1100-4gltena_integrated_services_router:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:1100-6g_integrated_services_router:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:1100-lte_integrated_services_router:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:1100_integrated_services_router:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:csr1000v:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
- cpe:2.3:h:cisco:4321_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:4331_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:4351_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:4431_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:1100-4g_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:1100-4gltegb_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:1100-4gltena_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:1100-6g_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:1100-lte_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:1100_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:csr1000v:-:*:*:*:*:*:*:* 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-2021-34723
- 2026-10-03 Alias added: GHSA-66cj-3q7r-633r
References
More Cisco Ios Xe vulnerabilities
- TI-2023-06904 Cisco is providing an update for the ongoing investigation into observed exploitation of… KEVCVSS 3.1CRITICAL 10.0
- TI-2018-00122 Memory corruption in Cisco IOS and IOS XE KEVCVSS 3.1CRITICAL 9.8
- TI-2017-02977 Improper input validation in Cisco IOS and IOS XE Software KEVCVSS 3.1CRITICAL 9.8
- TI-2018-00135 Memory corruption in Cisco IOS, IOS XE, and IOS XR KEVCVSS 3.1HIGH 8.8
- TI-2017-04498 Memory corruption in Cisco IOS KEVCVSS 3.1HIGH 8.8
- TI-2017-04497 Memory corruption in Cisco IOS XE Software KEVCVSS 3.1HIGH 8.8
Sources
- CVE-2021-34723 · CVE Program
- CVE-2021-34723 · NVD
- FIRST EPSS
- GHSA-66cj-3q7r-633r · 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