CVE-2026-42055
highpriority · track · 12EPSS 0.065 · 94 %ileexploit · PoCDEEURUUSEPSS · scored 2026-10-27
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_proxy_v2_module and ngx_http_grpc_module modules. This vulnerability exists when the proxy_http_version to 2 or grpc_pass directives are used to proxy HTTP/2 traffic, the ignore_invalid_headers directive is set to off, and the large_client_header_buffers directive size is larger than 2 megabytes. A remote, unauthenticated attacker, along with conditions beyond their control, could send large headers while creating an upstream request. This may cause a heap-based buffer overflow in the NGINX worker process leading to a restart. Additionally, attackers can execute code on systems with Address Space Layout Randomization (ASLR) disabled or when the attacker can bypass ASLR. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 8.1–9.2
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
exploits (1)
Public proof-of-concept and weaponised exploit code.
- HORKimhab/CVE-2026-42055CVE-2026-42055 - DraftPoC · poc_in_github
affected products (69)
Products and version ranges known to be affected.
advisories (4)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-1995NGINX und NGINX Plus: Mehrere SchwachstellenDeutsch2026-06-17csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in NGINX und NGINX NGINX Plus ausnutzen, um Daten zu manipulieren, beliebigen Code auszuführen, vertrauliche Informationen offenzulegen oder einen Denial-of-Service-Zustand auszulösen.
- BIT-nginx-2026-42055NGINX ngx_http_proxy_v2_module and ngx_http_grpc_module vulnerability2026-06-22vendor · osvUS
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_proxy_v2_module and ngx_http_grpc_module modules. This vulnerability exists when the proxy_http_version to 2 or grpc_pass directives are used to proxy HTTP/2 traffic, the ignore_invalid_headers directive is set to off, and the large_client_header_buffers directive size is larger than 2 megabytes. A remote, unauthenticated attacker, along with conditions beyond their control, could send large headers while creating an upstream request. This may cause a heap-based buffer overflow in the NGINX worker process leading to a restart. Additionally, attackers can execute code on systems with Address Space Layout Randomization (ASLR) disabled or when the attacker can bypass ASLR. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
- BIT-nginx-gateway-2026-42055NGINX ngx_http_proxy_v2_module and ngx_http_grpc_module vulnerability2026-06-22vendor · osvUS
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_proxy_v2_module and ngx_http_grpc_module modules. This vulnerability exists when the proxy_http_version to 2 or grpc_pass directives are used to proxy HTTP/2 traffic, the ignore_invalid_headers directive is set to off, and the large_client_header_buffers directive size is larger than 2 megabytes. A remote, unauthenticated attacker, along with conditions beyond their control, could send large headers while creating an upstream request. This may cause a heap-based buffer overflow in the NGINX worker process leading to a restart. Additionally, attackers can execute code on systems with Address Space Layout Randomization (ASLR) disabled or when the attacker can bypass ASLR. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
- BIT-nginx-gateway-fabric-2026-42055NGINX ngx_http_proxy_v2_module and ngx_http_grpc_module vulnerability2026-07-27vendor · osvUS
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_proxy_v2_module and ngx_http_grpc_module modules. This vulnerability exists when the proxy_http_version to 2 or grpc_pass directives are used to proxy HTTP/2 traffic, the ignore_invalid_headers directive is set to off, and the large_client_header_buffers directive size is larger than 2 megabytes. A remote, unauthenticated attacker, along with conditions beyond their control, could send large headers while creating an upstream request. This may cause a heap-based buffer overflow in the NGINX worker process leading to a restart. Additionally, attackers can execute code on systems with Address Space Layout Randomization (ASLR) disabled or when the attacker can bypass ASLR. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
also known as (7)
Other names and identifiers for this entity.
- CNNVD-2026-85431872cnnvd
- EUVD-2026-37718enisa_euvd
- BDU:2026-08881fstec_bdu
- GHSA-78jw-ww3g-9wp7enisa_euvd
- BIT-nginx-2026-42055osv
- BIT-nginx-gateway-2026-42055osv
- BIT-nginx-gateway-fabric-2026-42055osv
sources
Which sources assert this record, and when.
references (15)
External citations — patches, advisories, analysis.
- https://my.f5.com/manage/s/article/K000161584cnnvd
- https://my.f5.com/manage/s/article/K000161584enisa_euvd
- https://access.redhat.com/errata/RHSA-2026:27197Third Party Advisorynvd
- https://access.redhat.com/errata/RHSA-2026:36331Third Party Advisorynvd
- https://access.redhat.com/errata/RHSA-2026:36364Third Party Advisorynvd
- https://access.redhat.com/errata/RHSA-2026:36618Third Party Advisorynvd
- https://access.redhat.com/errata/RHSA-2026:36639Third Party Advisorynvd
- https://access.redhat.com/errata/RHSA-2026:38847Third Party Advisorynvd
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