CVE-2017-12309

CVE-2017-12309 is a medium-severity vulnerability in Cisco Email Security Appliance Firmware with a CVSS 3.x base score of 5.3. 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-113.

Key facts

Description

A vulnerability in the Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to conduct a HTTP response splitting attack. The vulnerability is due to the failure of the application or its environment to properly sanitize input values. An attacker could exploit this vulnerability by injecting malicious HTTP headers, controlling the response body, or splitting the response into multiple responses. An exploit could allow the attacker to perform cross-site scripting attacks, cross-user defacement, web cache poisoning, and similar exploits. Cisco Bug IDs: CSCvf16705.

Frequently asked questions

What is CVE-2017-12309?
A vulnerability in the Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to conduct a HTTP response splitting attack. The vulnerability is due to the failure of the application or its environment to properly sanitize input values. An attacker could exploit this vulnerability by injecting malicious HTTP headers, controlling the response body, or splitting the response into multiple responses. An exploit could allow the attacker to perform cross-site scripting attacks, cross-user defacement, web cache poisoning, and similar exploits. Cisco Bug IDs: CSCvf16705.
How severe is CVE-2017-12309?
CVE-2017-12309 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2017-12309 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-12309?
CVE-2017-12309 primarily affects Cisco Email Security Appliance Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2017-12309?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2017-12309 published?
CVE-2017-12309 was published on 2017-11-16 and last updated on 2026-06-17.

References

Affected products (2)

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