Severity by source
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/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
AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
Primary rating from Vendor (f5).
CVSS VectorVendor: f5
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/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
Lifecycle Timeline
3DescriptionCVE.org
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_charset_module module. When charset, source_charset, and charset_map and proxy_pass with disabled buffering ("off") directives are configured, unauthenticated attackers can send requests that with conditions beyond the attackers' control to cause a heap buffer over-read in the NGINX worker process, leading to limited disclosure of memory or a restart.
Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
AnalysisAI
Heap buffer over-read in NGINX's ngx_http_charset_module allows unauthenticated remote attackers to leak sensitive memory or crash worker processes when specific configuration directives (charset, source_charset, charset_map, and proxy_pass with buffering disabled) are combined. The vulnerability requires attacker-controlled conditions that depend on factors outside the attacker's control, limiting exploitability but creating real risk for affected deployments. CVSS 4.8 reflects the conditional nature of exploitation and limited scope of impact (information disclosure or availability).
Technical ContextAI
The ngx_http_charset_module in NGINX handles character set encoding transformations and charset mapping between client requests and upstream responses. The vulnerability is a classic heap buffer over-read (CWE-125) occurring in the charset conversion logic when proxy_pass with disabled buffering ('off') is combined with charset mapping directives. The over-read allows an attacker to read adjacent heap memory beyond the intended buffer boundary. The underlying issue stems from insufficient bounds checking during character encoding operations, particularly when the module must process charset transformations on data flowing through a non-buffered proxy connection. Both NGINX Plus (commercial) and NGINX Open Source are affected, as identified by CPE strings cpe:2.3:a:f5:nginx_plus:*:*:*:*:*:*:*:* and cpe:2.3:a:f5:nginx_open_source:*:*:*:*:*:*:*:*.
RemediationAI
Apply the vendor-released patch from F5 (https://my.f5.com/manage/s/article/K000161028) immediately for affected NGINX Plus and NGINX Open Source installations. The patch addresses bounds checking in the ngx_http_charset_module. If patching cannot be immediately deployed, implement compensating controls by removing or disabling the combination of directives that triggers the vulnerability: specifically, comment out or remove charset_map directives and/or disable charset transformation (charset off; source_charset off;) in affected server blocks, OR convert proxy_pass connections to use proxy buffering enabled (remove 'off' flag or set proxy_buffering on;). Disabling buffering may impact performance or caching behavior if proxy_buffering was intentionally disabled for streaming use cases, so test thoroughly before production deployment. Monitor NGINX error logs for worker process crashes (SIGSEGV) which may indicate exploitation attempts or edge cases in the patch.
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Heap buffer overflow in NGINX Plus and NGINX Open Source lets unauthenticated remote attackers crash worker processes (D
Buffer overflow in NGINX's DAV module allows remote attackers to crash worker processes or manipulate file names outside
Limited memory disclosure and worker-process restart in NGINX Plus and NGINX Open Source arise when the optional ngx_htt
NGINX worker process crashes via null pointer dereference in the mail authentication module when CRAM-MD5 or APOP authen
When the NGINX Plus is configured to use the MQTT pre-read module, undisclosed requests can cause an increase in memory
NGINX Open Source and NGINX Plus contain a buffer over-read or over-write vulnerability in the ngx_http_mp4_module that
Memory disclosure and denial-of-service in NGINX's SCGI and uWSGI proxy modules allow attackers with man-in-the-middle p
Heap buffer over-read in the ngx_http_ssi_module of NGINX Open Source and NGINX Plus lets an unauthenticated man-in-the-
When NGINX Plus or NGINX OSS are configured to use the HTTP/3 QUIC module, undisclosed requests can cause NGINX worker p
Same weakness CWE-125 – Out-of-bounds Read
View allSame technique Information Disclosure
View allVendor StatusVendor
SUSE
Severity: Medium| Product | Status |
|---|---|
| SUSE Linux Enterprise High Performance Computing 15 SP7 SUSE Linux Enterprise Module for Server Applications 15 SP7 SUSE Linux Enterprise Server 15 SP7 SUSE Linux Enterprise Server for SAP Applications 15 SP7 | Fixed |
| SUSE Linux Enterprise Server 15 SP6-LTSS | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | Fixed |
| openSUSE Tumbleweed | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Server 16.0 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | Affected |
| SUSE Manager Proxy LTS 4.3 | Affected |
| SUSE Manager Retail Branch Server LTS 4.3 | Affected |
| SUSE Manager Server LTS 4.3 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP7 | Fixed |
| SUSE Linux Enterprise Module for Server Applications 15 SP7 | Fixed |
| SUSE Linux Enterprise Server 15 SP7 | Fixed |
| SUSE Linux Enterprise Server 16.0 | Fixed |
| SUSE Linux Enterprise Server 16.1 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | Fixed |
| SUSE Linux Enterprise Server for SAP applications 16.1 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP4 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP5 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | Fixed |
| SUSE Linux Enterprise Module for Server Applications 15 SP4 | Fixed |
| SUSE Linux Enterprise Module for Server Applications 15 SP5 | Fixed |
| SUSE Linux Enterprise Module for Server Applications 15 SP6 | Fixed |
| SUSE Linux Enterprise Server 15 SP4 | Fixed |
| SUSE Linux Enterprise Server 15 SP4-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP5 | Fixed |
| SUSE Linux Enterprise Server 15 SP5-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP6 | Fixed |
| SUSE Linux Enterprise Server 15 SP6-LTSS | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | Fixed |
| SUSE Manager Proxy 4.3 | Fixed |
| SUSE Manager Proxy LTS 4.3 | Fixed |
| SUSE Manager Retail Branch Server 4.3 | Fixed |
| SUSE Manager Retail Branch Server LTS 4.3 | Fixed |
| SUSE Manager Server 4.3 | Fixed |
| SUSE Manager Server LTS 4.3 | Fixed |
| SUSE CaaS Platform 4.0 | Fixed |
| SUSE Enterprise Storage 6 | Fixed |
| SUSE Enterprise Storage 7 | Fixed |
| SUSE Enterprise Storage 7.1 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP1 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP2 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP3 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP6 | Fixed |
| SUSE Linux Enterprise Module for Server Applications 15 SP1 | Fixed |
| SUSE Linux Enterprise Module for Server Applications 15 SP2 | Fixed |
| SUSE Linux Enterprise Module for Server Applications 15 SP3 | Fixed |
| SUSE Linux Enterprise Real Time 15 SP2 | Fixed |
| SUSE Linux Enterprise Real Time 15 SP3 | Fixed |
| SUSE Linux Enterprise Real Time 15 SP4 | Fixed |
| SUSE Linux Enterprise Server 15 SP1 | Fixed |
| SUSE Linux Enterprise Server 15 SP1-BCL | Fixed |
| SUSE Linux Enterprise Server 15 SP1-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP2 | Fixed |
| SUSE Linux Enterprise Server 15 SP2-BCL | Fixed |
| SUSE Linux Enterprise Server 15 SP2-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP3 | Fixed |
| SUSE Linux Enterprise Server 15 SP3-BCL | Fixed |
| SUSE Linux Enterprise Server 15 SP3-LTSS | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP1 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP2 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP3 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | Fixed |
| SUSE Manager Proxy 4.0 | Fixed |
| SUSE Manager Proxy 4.1 | Fixed |
| SUSE Manager Proxy 4.2 | Fixed |
| SUSE Manager Retail Branch Server 4.0 | Fixed |
| SUSE Manager Retail Branch Server 4.1 | Fixed |
| SUSE Manager Retail Branch Server 4.2 | Fixed |
| SUSE Manager Server 4.0 | Fixed |
| SUSE Manager Server 4.1 | Fixed |
| SUSE Manager Server 4.2 | Fixed |
| openSUSE Leap 15.3 | Fixed |
| openSUSE Leap 15.4 | Fixed |
| openSUSE Leap 15.5 | Fixed |
| openSUSE Leap 15.6 | Fixed |
| suse/rmt-nginx | Fixed |
| private-registry/harbor-nginx suse/nginx | Fixed |
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External POC / Exploit Code
Leaving vuln.today
EUVD-2026-30008
GHSA-6vmc-2wh4-77qp