Medium 4.8Published May 13, 2026

CVE-2026-42934NGINX ngx_http_charset_module vulnerability

Updated under an hour ago (Oct 26, 2026, 11:10 PM ET)

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It affects F5 NGINX Plus and 6 other products. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for F5 NGINX Plus

Exploited in the last 30 days

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.

CVSS: 4.8 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
Weakness (CWE): CWE-125
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: f5
NVD analysis: Analyzed
Record last updated: Jun 8, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

F5 NGINX Plus f5:nginx_plus (from the name)	from R37 not affected; from R36 before R36 P4; from R32 before R32 P6	CNA record
F5 NGINX Open Source f5:nginx_open_source (from the name)	from 1.31.0 not affected; from 0.3.50 before 1.30.1	CNA record
f5 dos f5:dos	from 4.3.0 through 4.7.0; 4.8.0	NVD
f5 nginx_gateway_fabric f5:nginx_gateway_fabric	from 1.3.0 through 1.6.2; from 2.0.0 through 2.6.0	NVD
f5 nginx_ingress_controller f5:nginx_ingress_controller	from 3.5.0 through 3.7.2; from 4.0.0 through 4.0.1; from 5.0.0 through 5.4.2	NVD
f5 nginx_instance_manager f5:nginx_instance_manager	from 2.16.0 through 2.22.0	NVD
f5 nginx_open_source f5:nginx_open_source	from 0.3.50 through 0.9.7; from 1.0.0 through 1.30.0	NVD
f5 nginx_plus f5:nginx_plus	from r32 through r36	NVD
f5 waf f5:waf	from 4.9.0 through 4.16.0; from 5.1.0 through 5.8.0; from 5.9.0 through 5.12.1	NVD

References

References

https://my.f5.com/manage/s/article/K000161028	vendor-advisory, patch, mitigation

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.