Buffer overflow in F5 Dos
CVE-2026-42945
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_rewrite_module module. This vulnerability exists when the rewrite directive is followed by a rewrite, if, or set directive and an unnamed Perl-Compatible Regular Express…
Vulnerability class: Buffer Overflow
EPSS: 0.615 (99.1th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.
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, 0.6.27
- F5 Nginx_open_source
- F5 Nginx Plus — versions R37, R36, R32
- F5 Nginx_plus
Weakness classification (CWE)
Public proof-of-concept exploits
References
- f5sirt@f5.com (vendor-advisory, Mitigation, patch, Vendor Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (Technical Description, Third Party Advisory, Mitigation)
- af854a3a-2127-422b-91ae-364da2661108 (Exploit, Third Party Advisory)
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Frequently asked questions
- What is CVE-2026-42945?
- CVE-2026-42945 is a high-severity vulnerability in F5 Dos, classified under Heap-based Buffer Overflow. CVSS score: 8.1/10. Published 2026-05-13.
- How severe is CVE-2026-42945?
- High severity. CVSS v3 base score is 8.1 out of 10.
- Is CVE-2026-42945 known to be exploited?
- 52 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.