CVE-2017-12310
CVE-2017-12310 is a high-severity vulnerability in Cisco Spark Hybrid Calendar Service with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-319.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 1% (56th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-319
- Affected product: Cisco Spark Hybrid Calendar Service
- Published:
- Last modified:
Description
A vulnerability in the auto discovery phase of Cisco Spark Hybrid Calendar Service could allow an unauthenticated, remote attacker to view sensitive information in the unencrypted headers of an HTTP method request. The attacker could use this information to conduct additional reconnaissance attacks leading to the disclosure of sensitive customer data. The vulnerability exists in the auto discovery phase because an unencrypted HTTP request is made due to requirements for implementing the Hybrid Calendar service. An attacker could exploit this vulnerability by monitoring the unencrypted traffic on the network. An exploit could allow the attacker to access sensitive customer data belonging to Office365 users, such as email and calendar events. Cisco Bug IDs: CSCvg35593.
Frequently asked questions
- What is CVE-2017-12310?
- A vulnerability in the auto discovery phase of Cisco Spark Hybrid Calendar Service could allow an unauthenticated, remote attacker to view sensitive information in the unencrypted headers of an HTTP method request. The attacker could use this information to conduct additional reconnaissance attacks leading to the disclosure of sensitive customer data. The vulnerability exists in the auto discovery phase because an unencrypted HTTP request is made due to requirements for implementing the Hybrid Calendar service. An attacker could exploit this vulnerability by monitoring the unencrypted traffic on the network. An exploit could allow the attacker to access sensitive customer data belonging to Office365 users, such as email and calendar events. Cisco Bug IDs: CSCvg35593.
- How severe is CVE-2017-12310?
- CVE-2017-12310 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
- Is CVE-2017-12310 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2017-12310?
- CVE-2017-12310 affects Cisco Spark Hybrid Calendar Service. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2017-12310?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2017-12310 published?
- CVE-2017-12310 was published on 2018-03-27 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:cisco:spark_hybrid_calendar_service:*:*:*:*:*:*:*:*
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