CVE-2026-76519: Cisco Secure Email Gateway Relative Path Traversal Vulnerability
- Is it exploited?
Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 14 Oct 2026, the same day the CVE record was published.
- How likely is exploitation in the next 30 days?
- 2.2%
EPSS score, percentile 82.1 of all scored records
- How severe?
- 9.8 Critical
CVSS v3.1 base score, given by the CNA
- What should I do?
CISA deadline 17 Oct 2026. Apply mitigations in accordance with vendor instructions … Full text
The CVE record links no vendor advisory, patch or mitigation.
- Which versions are affected?
Affected
- 14.0.0-698
- 13.5.1-277
- 13.0.0-392
- 14.2.0-620
- 13.0.5-007
- 13.5.4-038
and 6 more in the table below
Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.
What to do
Required action, set by CISA
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
CISA due date for this action: 17 October 2026.
Advisories and patches
The CVE record links no vendor advisory, patch or mitigation.
Linked from CISA's catalog entry
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-esa-afw-zqYJkjxp
- https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk
- https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk
- https://nvd.nist.gov/vuln/detail/CVE-2026-76519
Affected products and versions
As listed in the CVE record.
| Status | Versions |
|---|---|
| Affected | 14.0.0-698 |
| Affected | 13.5.1-277 |
| Affected | 13.0.0-392 |
| Affected | 14.2.0-620 |
| Affected | 13.0.5-007 |
| Affected | 13.5.4-038 |
| Affected | 14.2.1-020 |
| Affected | 14.3.0-032 |
| Affected | 15.0.0-104 |
| Affected | 15.0.1-030 |
| Affected | 15.5.0-048 |
| Affected | 15.5.1-055 |
Versions not listed are: unknown.
And 11 more version entries in the CVE record.
Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.
About this vulnerability
Cisco Secure Email Gateway contains a relative path traversal vulnerability that could allow an unauthenticated, remote attacker to write arbitrary files on the underlying operating system.
Summary: CISA's KEV catalog, as of 28 Oct 2026.
- CISA added CVE-2026-76519 to its Known Exploited Vulnerabilities (KEV) catalog on 14 Oct 2026.
- CISA's ransomware flag for this entry is "Unknown": no evidence of ransomware use in the catalog, which is not proof of none.
- The due date CISA sets for the required action is 17 Oct 2026.
- The CVE record was published on 14 Oct 2026, the same day it was added to KEV.
- The CVE record carries a CVSS v3.1 base score of 9.8 (Critical), given by its CNA.
- FIRST's EPSS model puts the probability of exploitation in the next 30 days at 2.2% (percentile 82.1), as of 28 Oct 2026.
- CISA's SSVC assessment in the CVE record: exploitation active, automatable yes, technical impact total.
Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.
Description
Cisco Secure Email Gateway Arbitrary File Write Vulnerability
A vulnerability in the Advanced Malware Protection (AMP) feature of Cisco Secure Email Gateway could allow an unauthenticated, remote attacker to write arbitrary files on the underlying operating system. This vulnerability is due to improper handling of email attachments when the file reputation service is enabled. An attacker could exploit this vulnerability by sending an email that contains a crafted attachment through an affected device. A successful exploit could allow the attacker to write arbitrary files and execute commands with root privileges on the underlying operating system.
Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.
Weakness
CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.
Timeline
| Date | Event |
|---|---|
| 14 Oct 2026 | CVE record published |
| 14 Oct 2026 | Added to CISA KEV |
| 15 Oct 2026 | CVE record last updated |
| 17 Oct 2026 | CISA due date for the required action |
References
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