A vulnerability in the implementation of Session Initiation Protocol (SIP) functionality in Cisco Small Business SPA50x, SPA51x, and SPA52x Series IP Phones could allow an unauthenticated, remote attacker to cause an affected device to become unresponsive, resulting in a denial of service (DoS) condition
Published Oct 19, 2017
7.5
HIGHCVSS 3.0
EPSS 2.30%
Description
A vulnerability in the implementation of Session Initiation Protocol (SIP) functionality in Cisco Small Business SPA50x, SPA51x, and SPA52x Series IP Phones could allow an unauthenticated, remote attacker to cause an affected device to become unresponsive, resulting in a denial of service (DoS) condition. The vulnerability is due to the improper handling of SIP request messages by an affected device. An attacker could exploit this vulnerability by using formatted specifiers in a SIP payload that is sent to an affected device. A successful exploit could allow the attacker to cause the affected device to become unresponsive, resulting in a DoS condition that persists until the device is restarted manually. This vulnerability affects Cisco Small Business SPA50x, SPA51x, and SPA52x Series IP Phones that are running firmware release 7.6.2SR1 or earlier. Cisco Bug IDs: CSCvc63986.
Affected products
- Vendor n/a Product Cisco Small Business SPA50x, SPA51x, and SPA52x Series IP Phones Defaultn/a
- Version Cisco Small Business SPA50x, SPA51x, and SPA52x Series IP PhonesStatusaffectedConstraints-
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| n/a | Cisco Small Business SPA50x, SPA51x, and SPA52x Series IP Phones | n/a |
|
Configuration 1
- ≤ 7.6.2
Configuration 2
- ≤ 7.6.2
Configuration 3
- ≤ 7.6.2
Configuration 4
- ≤ 7.6.2
Configuration 5
- ≤ 7.6.2
Configuration 6
- ≤ 7.6.2
Configuration 7
- ≤ 7.6.2
Configuration 8
- ≤ 7.6.2
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
AV:N/AC:L/Au:N/C:N/I:N/A:P
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2021–2026- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Percentile over time
- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Table of values (10 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 2.30% (0.02297) | 82.66th | v5 (v2026.06.15) |
| Jun 15, 2026 | 2.30% (0.02297) | 80.96th | v5 (v2026.06.15) |
| Mar 17, 2025 | 1.12% (0.01121) | 76.73th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.24% (0.00236) | 62.63th | v3 (v2023.03.01) |
| Sep 3, 2023 | 0.24% (0.00236) | 61.06th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.39% (0.00385) | 68.92th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.14% (0.01136) | 59.45th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.14% (0.01136) | 34.23th | v2 (v2022.01.01) |
| Feb 3, 2022 | 1.30% (0.01300) | 31.12th | v5 (v2026.06.15) |
| Apr 14, 2021 | 1.30% (0.01300) | 0.00th | v1 |
References (3)
- http://www.securityfocus.com/bid/101495 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- http://www.securitytracker.com/id/1039616 vdb-entryx_refsource_SECTRACKThird Party AdvisoryVDB Entry
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20171018-sip1 x_refsource_CONFIRMVendor Advisory
| Link | Providers | Tags |
|---|---|---|
| http://www.securityfocus.com/bid/101495 | vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry | |
| http://www.securitytracker.com/id/1039616 | vdb-entryx_refsource_SECTRACKThird Party AdvisoryVDB Entry | |
| https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20171018-sip1 | x_refsource_CONFIRMVendor Advisory |
Change history (0)
No recorded changes yet.