Cisco IP Phone TCP Packet Flood Denial of Service Vulnerability
Noroxi assessment
Priority: Monitor (action score 32/100)
- 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: 8% (FIRST EPSS); higher than 94.7% of all records.
- Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
- According to CISA the attack is automatable: targets can be found by mass scanning.
- 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 TCP packet processing functionality of Cisco IP Phones could allow an unauthenticated, remote attacker to cause the phone to stop responding to incoming calls, drop connected calls, or unexpectedly reload. The vulnerability is due to insufficient TCP ingress packet rate limiting. An attacker could exploit this vulnerability by sending a high and sustained rate of crafted TCP traffic to the targeted device. A successful exploit could allow the attacker to impact operations of the phone or cause the phone to reload, leading to a denial of service (DoS) condition.
- Published
- Nov 6, 2020
- Updated
- Jun 16, 2026
- EPSS
- 8.0% · 94th percentile
- CWE
- CWE-371
Report tools
Action score
32
Monitor
Low priority for now.
- CVSS
- 30 / 40 · 7.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 2 / 30 · 8.0%
CISA SSVC decision
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- 7.5
- CNA · cisco
- 7.5
- 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.
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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.
We use this product, ask for helpAffected 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.
| Vendor | Product | CPE |
|---|---|---|
| cisco | ip dect 210 firmware | cpe:2.3:o:cisco:ip_dect_210_firmware |
| cisco | ip dect 210 | cpe:2.3:h:cisco:ip_dect_210 |
| cisco | ip dect 6825 firmware | cpe:2.3:o:cisco:ip_dect_6825_firmware |
| cisco | ip dect 6825 | cpe:2.3:h:cisco:ip_dect_6825 |
| cisco | ip phone 8811 firmware | cpe:2.3:o:cisco:ip_phone_8811_firmware |
| cisco | ip phone 8811 | cpe:2.3:h:cisco:ip_phone_8811 |
| cisco | ip phone 8841 firmware | cpe:2.3:o:cisco:ip_phone_8841_firmware |
| cisco | ip phone 8841 | cpe:2.3:h:cisco:ip_phone_8841 |
| cisco | ip phone 8851 firmware | cpe:2.3:o:cisco:ip_phone_8851_firmware |
| cisco | ip phone 8851 | cpe:2.3:h:cisco:ip_phone_8851 |
| cisco | ip phone 8861 firmware | cpe:2.3:o:cisco:ip_phone_8861_firmware |
| cisco | ip phone 8861 | cpe:2.3:h:cisco:ip_phone_8861 |
and 4 more
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- cisco ip dect 210 firmwarebefore 4.8.1
- cisco ip dect 6825 firmwarebefore 4.8.1
- cisco ip phone 8811 firmwarebefore 11.3.2
- cisco ip phone 8841 firmwarebefore 11.3.2
- cisco ip phone 8851 firmwarebefore 11.3.2
- cisco ip phone 8861 firmwarebefore 11.3.2
- cisco unified ip conference phone 8831 firmware9.3(4)
- cisco webex room phone firmwarebefore 1.2.0
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 IP Phones with Multiplatform Firmware
- n/aaffected
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.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
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 researchersFinders, 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
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- none
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- High
Weakness class (CWE)
CWE-371 · State IssuesCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.
References
- tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-voip-phone-flood-dos-YnU9EXOv
Vendor advisories and official records. Exploit/PoC links are deliberately left out.