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CVE

CVE-2026-42055

NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_proxy_v2_module and ngx_http_grpc_module modules.
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CVE

CVE-2026-42055

NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_proxy_v2_module and ngx_http_grpc_module modules.

NGINX Plus and NGINX Open Source have a vulnerability in the ngxhttpproxyv2module and ngxhttpgrpcmodule modules. This vulnerability exists when the proxyhttpversion to 2 or grpcpass directives are used to proxy HTTP/2 traffic, the ignoreinvalidheaders directive is set to off, and the largeclientheader_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. 

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Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Package Versions Affected

Package Version
patch Availability
No items found.

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CVSS Version

Severity
Base Score
CVSS Version
Score Vector
C
H
U
9.2
-
4.0
CVSS:4.0/AV:N/AC:H/AT:P/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:X
C
H
U
0
-
C
H
U
-

Related Resources

No items found.

References

https://access.redhat.com/errata/RHSA-2026:27197, https://access.redhat.com/errata/RHSA-2026:36331, https://access.redhat.com/errata/RHSA-2026:36364, https://access.redhat.com/errata/RHSA-2026:36618, https://access.redhat.com/errata/RHSA-2026:36639, https://access.redhat.com/errata/RHSA-2026:38847, https://access.redhat.com/errata/RHSA-2026:44481, https://access.redhat.com/errata/RHSA-2026:46836, https://access.redhat.com/security/cve/CVE-2026-42055, https://my.f5.com/manage/s/article/K000161584, https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42055.json, https://bugzilla.redhat.com/show_bug.cgi?id=2489866

Severity

0

CVSS Score
0
10

Basic Information

Base CVSS
0
EPSS Probability
0.04022%
EPSS Percentile
0.89782%
Introduced Version
e8053c867f9ab14f323e3019ccab585d857abb66,7dad8b31e3f0c3eadce36fed8c276e83e6583d24,0
Fix Available
1:1.24.0-3.module+el8.10.0+24503+61c7c092.3,1:1.24.0-7.module+el9.8.0+24502+c9b9ab67.3,2:1.26.3-9.module+el9.8.0+24501+a1e882cd.2,2:1.20.1-28.el9_8.4,1.22.1-9+deb12u9,1.18.0-6.1+deb11u8,1.26.3-3+deb13u7,1.24.0-2ubuntu7.13,1.18.0-6ubuntu14.16,1.28.3-r4,1.26.3-r2,1:1.24.0-3.0.1.module+el8.10.0+90952+25c71254.3,2:1.20.1-28.0.1.el9_8.4,2:1.26.3-9.0.1.module+el9.8.0+90950+a1e882cd.2,1:1.24.0-7.0.1.module+el9.8.0+90951+a848b39d.3,1:1.30.3-1.amzn2.0.1,1:1.30.3-1.amzn2023.0.1,1.15.8-r0,1.31.2-r0,1.30.3-r0

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