CVE-2026-56434

mediumpriority · track · 0EPSS 0.004 · 36 %ileDEEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.42% (36th) EPSS

CVSS 6.5 · medium

Is it mine?

66 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · osv

EPSS · scored 2026-10-27

NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_ssi_module module. This vulnerability may exist when the Server-Side Includes (SSI), proxy_pass, and proxy_buffering off directives are configured. With this configuration, an unauthenticated attacker with man-in-the-middle (MITM) ability to control responses from an upstream server may be able to cause a use-after-free in the NGINX worker process. This issue may lead to limited modification of memory or a restart of the NGINX worker process. Impact: This vulnerability may allow remote attackers to have limited control to modify memory contents or restart the NGINX worker process. There is no control plane exposure; this is a data plane issue only. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

cvss

Technical severity, 0–10. One row per scoring source.

8.3

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.8–8.3

v3.16.5mediumAV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:Hsecondary · FSTEC (BDU) RU

v3.16.5mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:Hsecondary · f5sirt@f5.comexploitability 2.2 · impact 4.2

v4.08.3highCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:Nsecondary · ENISA EU

v4.08.3highCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Xsecondary · f5sirt@f5.com

v4.04.8mediumCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Xsecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-416USCWE-416US

affected products (66)

Products and version ranges known to be affected.

Amazon Linux 2all versionscert_bundDEcpe:/o:amazon:linux_2:-
Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
Fedora Linuxall versionscert_bundDEcpe:/o:fedoraproject:fedora:-
Gentoo Linuxall versionscert_bundDEcpe:/o:gentoo:linux:-
Oracle Linuxall versionscert_bundDEcpe:/o:oracle:linux:-
RESF Rocky Linuxall versionscert_bundDEcpe:/o:resf:rocky_linux:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
SUSE Linuxall versionscert_bundDEcpe:/o:suse:suse_linux:-
SUSE openSUSEall versionscert_bundDEcpe:/o:suse:opensuse:-
Ubuntu Linuxall versionscert_bundDEcpe:/o:canonical:ubuntu_linux:-
NGINX NGINX Plus< 37.0.3.1cert_bundDE
NGINX NGINX Plus< R36 P7cert_bundDE
F5 NGINX Open Source0.8.11 → 1.30.4enisa_euvdEU
F5 NGINX Open Source1.31.2 → 1.31.3enisa_euvdEU
F5 NGINX Plus37.0.0.1 → 37.0.3.1enisa_euvdEU
F5 NGINX PlusR33 → *enisa_euvdEU
F5 NGINX PlusR36 → R36 P7enisa_euvdEU
Canonical Ltd. Ubuntu≤ 22.04 LTSfstec_bduRU
Canonical Ltd. Ubuntu≤ 24.04 LTSfstec_bduRU
Canonical Ltd. Ubuntu≤ 26.04 LTSfstec_bduRU

showing 20 of 66

advisories (3)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2026-2383NGINX NGINX Plus: Mehrere SchwachstellenDeutsch2026-07-15csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in NGINX NGINX Plus ausnutzen, um beliebigen Programmcode auszuführen, um einen Denial of Service Angriff durchzuführen, um Daten zu manipulieren, und um Informationen offenzulegen.
BIT-nginx-2026-56434NGINX ngx_http_ssi_module vulnerability2026-07-20vendor · osvUS
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_ssi_module module. This vulnerability may exist when the Server-Side Includes (SSI), proxy_pass, and proxy_buffering off directives are configured. With this configuration, an unauthenticated attacker with man-in-the-middle (MITM) ability to control responses from an upstream server may be able to cause a use-after-free in the NGINX worker process. This issue may lead to limited modification of memory or a restart of the NGINX worker process. Impact: This vulnerability may allow remote attackers to have limited control to modify memory contents or restart the NGINX worker process. There is no control plane exposure; this is a data plane issue only. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
BIT-nginx-gateway-2026-56434NGINX ngx_http_ssi_module vulnerability2026-07-20vendor · osvUS
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_ssi_module module. This vulnerability may exist when the Server-Side Includes (SSI), proxy_pass, and proxy_buffering off directives are configured. With this configuration, an unauthenticated attacker with man-in-the-middle (MITM) ability to control responses from an upstream server may be able to cause a use-after-free in the NGINX worker process. This issue may lead to limited modification of memory or a restart of the NGINX worker process. Impact: This vulnerability may allow remote attackers to have limited control to modify memory contents or restart the NGINX worker process. There is no control plane exposure; this is a data plane issue only. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

also known as (6)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu osv cert_bund NVD CVE.org MITRE

published 2026-07-15modified 2026-08-10

references (3)

External citations — patches, advisories, analysis.

scry

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