Resource exhaustion in Gophish
CVE-2026-39904
Gophish through 0.12.1 contains a denial of service vulnerability that allows authenticated users with the User role to exhaust server memory by uploading a crafted Office document as an email template attachment. The ApplyTemplate() function in models/attachment.go processes Office documents as ZIP archives and calls ioutil.ReadAll() on each contained file entry without enforcing size restrictions on uncompressed content, allowing a zip bomb payload to expand to several gigabytes in memory and cause the process to be terminated by the operating system.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.004 (35.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 36th percentile — 35.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Gophish — versions 0
Weakness classification (CWE)
References
- github.com/ashikmd7/GoPhish-0.12.1/blob/main/Unbounded Memory Allocation in Off… (technical-description, exploit)
- www.vulncheck.com/advisories/gophish-denial-of-service-via-office-document-uplo… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-39904?
- CVE-2026-39904 is a medium-severity vulnerability in Gophish, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 6.5/10. Published 2026-06-22.
- How severe is CVE-2026-39904?
- Medium severity. CVSS v3 base score is 6.5 out of 10.