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NVD / CVE Program· CNA cisco

CVE-2021-34724: Cisco IOS XE SD-WAN Software Privilege Escalation Vulnerability

Noroxi assessment

Priority: Monitor (action score 24/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.26% (FIRST EPSS).
  • Someone with local access to the system can trigger it. Administrator privileges are required. No user action is required. No special conditions are required; it is repeatable.
  • According to the record, no fixed version is available yet.

Low priority for now. Update when a fix is released; follow the vendor's advisory.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

A vulnerability in the Cisco IOS XE SD-WAN Software CLI could allow an authenticated, local attacker to elevate privileges and execute arbitrary code on the underlying operating system as the root user. An attacker must be authenticated on an affected device as a PRIV15 user. This vulnerability is due to insufficient file system protection and the presence of a sensitive file in the bootflash directory on an affected device. An attacker could exploit this vulnerability by overwriting an installer file stored in the bootflash directory with arbitrary commands that can be executed with root-level privileges. A successful exploit could allow the attacker to read and write changes to the configuration database on the affected device.

MediumCVSS 6.0 · v3.1—No exploit No fix recorded
Published
Sep 22, 2021
Updated
Jun 16, 2026
EPSS
0.2% · 18th percentile

Report tools

JSON

Action score

24

Monitor

Low priority for now.

CVSS
24 / 40 · 6.0 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.2%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
6.0
CNA · cisco
6.0
agree

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • No fixed version yet

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2021-34724

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
ciscoios xe sd-wan
cisco1000 integrated services router
cisco1100-4g\/6g integrated services router
cisco1100-4p integrated services router
cisco1100-8p integrated services router
cisco1100 integrated services router
cisco1101-4p integrated services router
cisco1101 integrated services router
cisco1109-2p integrated services router
cisco1109-4p integrated services router
cisco1109 integrated services router
cisco1111x-8p integrated services router

and 37 more

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • cisco ios xe sd-wanup to 17.3.1a inclusive

Versions reported by the vendor

Affected version ranges reported by the assigning authority (cisco). Independent of NVD's CPE analysis and usually ahead of it.

  • Cisco Cisco IOS XE SD-WAN Software

    • n/aaffected

Same product

cisco: all records

Other highest-scoring records for the same primary product.

  • CVE-2025-20352A vulnerability in the Simple Network Management Protocol (SNMP) subsystem of Cisco IOS Software and Cisco IOS XE Software could allow the fKEV
    72This week
  • CVE-2021-34727Cisco IOS XE SD-WAN Software Buffer Overflow Vulnerability
    40Plan
  • CVE-2021-1301Cisco SD-WAN Buffer Overflow Vulnerabilities
    40Plan

Published before and after this one in the same product

  • ← EarlierCVE-2021-1241Jan 20, 2021 · Cisco SD-WAN Denial of Service Vulnerabilities
    30Monitor
  • ← EarlierCVE-2021-1371Mar 24, 2021 · Cisco IOS XE SD-WAN Software Console Privilege Escalation Vulnerability
    26Monitor
  • Later →CVE-2021-34725Sep 22, 2021 · Cisco IOS XE SD-WAN Software Command Injection Vulnerability
    26Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

No fix version is recorded for this entry. Check the references for vendor advisories.

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • Administrator privileges are required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
none
Attack vector
Local
Attack complexity
Low
Privileges required
High
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
None

Weakness class (CWE)

CWE-284 · Improper Access Control

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Change log

No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.

References

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records