Vulnerability in F5 Dos
CVE-2026-42946
A vulnerability exists in the ngx_http_scgi_module and ngx_http_uwsgi_module modules that may result in excessive memory allocation or an over-read of data. When scgi_pass or uwsgi_pass is configured, an unauthenticated attacker with man-in-the-middle (MITM) ability to control responses from an upstream server may be able to read the memory of the NGINX worker process or restart it. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:L.
EPSS exploit prediction
EPSS: 0.009 (60.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 60th percentile — 60.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.009 · newest: 0.009 · change: 0.000
Affected products
- F5 Dos — versions 4.8.0
- F5 nginx App Protect Dos
- F5 nginx App Protect Waf
- F5 nginx Gateway Fabric
- F5 nginx Ingress Controller
- F5 nginx Instance Manager
- F5 nginx Open Source — versions 1.31.0, 0.8.42
- F5 nginx Open Source
- F5 nginx Plus — versions R37, R36, R32
- F5 nginx Plus
Weakness classification (CWE)
References
- my.f5.com/manage/s/article/K000161027 (vendor-advisory, Mitigation, patch, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-42946?
- CVE-2026-42946 is a medium-severity vulnerability in F5 Dos, classified under CWE-789. CVSS score: 6.5/10. Published 2026-05-13.
- How severe is CVE-2026-42946?
- Medium severity. CVSS v3 base score is 6.5 out of 10.