CVE-2026-42530

highpriority · track · 12EPSS 0.065 · 94 %ileexploit · PoCDEEURUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

3 exploits · PoC

Likely / severe?

6.45% (94th) EPSS

CVSS 8.1 · high

Is it mine?

31 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · osv

EPSS · scored 2026-10-27

NGINX Open Source has a vulnerability in the ngx_http_v3_module module. When NGINX Open Source is configured to use the HTTP/3 QUIC module, a remote unauthenticated attacker along with conditions beyond their control can use a specially crafted HTTP/3 session to reopen a QPACK encoder stream. This may cause a Use-after-Free 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.

9.2

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 8.1–9.2

v3.18.1highAV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.18.1highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · f5sirt@f5.comexploitability 2.2 · impact 5.9

v3.18.1highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondaryexploitability 2.2 · impact 5.9

v4.09.2criticalCVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:Nsecondary · ENISA EU

v4.09.2criticalCVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/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

v4.08.2highCVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/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.

Exploitation: none · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-416USCWE-416US

exploits (3)

Public proof-of-concept and weaponised exploit code.

0xBlackash/CVE-2026-42530CVE-2026-42530PoC · poc_in_github
HORKimhab/CVE-2026-42530CVE-2026-42530 - DraftPoC · poc_in_github
v4ltonn/CVE-2026-42530Scanner PoC for CVE-2026-42530 -- nginx 1.31.0-1.31.1 HTTP/3 QPACK encoder stream Use-After-Free (CVSS 9.2)PoC · poc_in_github

affected products (31)

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:-
Gentoo Linuxall versionscert_bundDEcpe:/o:gentoo:linux:-
NGINX NGINX Ingress Controllerall versionscert_bundDEcpe:/a:nginx:nginx:ingress_controller
NGINX NGINX Instance Managerall versionscert_bundDEcpe:/a:nginx:nginx:instance_manager
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:-
Nginx Nginx≤ Gateway Fabric <2.6.4cert_bundDE
Nginx Nginx≤ Open Source <1.31.2cert_bundDE
F5 NGINX Open Source1.31.0 → 1.31.2enisa_euvdEU
NGINX Inc. NGINX Gateway Fabric1.3.0 → 1.6.2fstec_bduRU
NGINX Inc. NGINX Gateway Fabric2.0.0 → 2.6.4fstec_bduRU
NGINX Inc. NGINX Ingress Controller3.5.0 → 3.7.2fstec_bduRU
NGINX Inc. NGINX Ingress Controller4.0.0 → 4.0.1fstec_bduRU
NGINX Inc. NGINX Ingress Controller5.0.0 → 5.5.1fstec_bduRU
NGINX Inc. NGINX Instance Manager2.17.0 → 2.22.0fstec_bduRU
NGINX Inc. NGINX Open Source1.31.0 → 1.31.2fstec_bduRU

showing 20 of 31

advisories (3)

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-2026-42530NGINX Open-Source ngx_http_v3_module vulnerability2026-06-22vendor · osvUS
NGINX Open Source has a vulnerability in the ngx_http_v3_module module. When NGINX Open Source is configured to use the HTTP/3 QUIC module, a remote unauthenticated attacker along with conditions beyond their control can use a specially crafted HTTP/3 session to reopen a QPACK encoder stream. This may cause a Use-after-Free 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-2026-42530NGINX Open-Source ngx_http_v3_module vulnerability2026-06-22vendor · osvUS
NGINX Open Source has a vulnerability in the ngx_http_v3_module module. When NGINX Open Source is configured to use the HTTP/3 QUIC module, a remote unauthenticated attacker along with conditions beyond their control can use a specially crafted HTTP/3 session to reopen a QPACK encoder stream. This may cause a Use-after-Free 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 (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 2026-06-17modified 2026-10-26

references (7)

External citations — patches, advisories, analysis.

https://my.f5.com/manage/s/article/K000161616 cnnvd
https://my.f5.com/manage/s/article/K000161616 enisa_euvd
https://access.redhat.com/errata/RHSA-2026:20351 nvd
https://access.redhat.com/security/cve/CVE-2026-42530Third Party Advisorynvd
https://bugzilla.redhat.com/show_bug.cgi?id=2489872Third Party Advisorynvd
https://my.f5.com/manage/s/article/K000161616Vendor Advisorynvd
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42530.jsonThird Party Advisorynvd

scry

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