{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-42934", "assignerOrgId": "9dacffd4-cb11-413f-8451-fbbfd4ddc0ab", "state": "PUBLISHED", "assignerShortName": "f5", "dateReserved": "2026-04-30T23:04:27.960Z", "datePublished": "2026-05-13T14:12:44.331Z", "dateUpdated": "2026-06-08T20:34:05.147Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "9dacffd4-cb11-413f-8451-fbbfd4ddc0ab", "shortName": "f5", "dateUpdated": "2026-06-08T20:34:05.147Z"}, "title": "NGINX ngx_http_charset_module vulnerability", "datePublic": "2026-05-13T14:00:00.000Z", "problemTypes": [{"descriptions": [{"lang": "en", "cweId": "CWE-125", "description": "CWE-125 Out-of-bounds Read", "type": "CWE"}]}], "affected": [{"vendor": "F5", "product": "NGINX Plus", "modules": ["ngx_http_charset_module"], "versions": [{"status": "unaffected", "version": "R37", "lessThan": "*", "versionType": "custom"}, {"status": "affected", "version": "R36", "lessThan": "R36 P4", "versionType": "custom"}, {"status": "affected", "version": "R32", "lessThan": "R32 P6", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "F5", "product": "NGINX Open Source", "modules": ["ngx_http_charset_module"], "versions": [{"status": "unaffected", "version": "1.31.0", "lessThan": "*", "versionType": "semver"}, {"status": "affected", "version": "0.3.50", "lessThan": "1.30.1", "versionType": "semver"}], "defaultStatus": "unaffected"}], "descriptions": [{"lang": "en", "value": "NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_charset_module module. 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{"bugzilla": {"description": "nginx: ngx_http_charset_module: information disclosure and denial of service", "id": "2477066", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2477066"}, "csaw": false, "cvss3": {"cvss3_base_score": "4.8", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L", "status": "draft"}, "cwe": "CWE-126", "details": ["A flaw was found in the ngx_http_charset_module module of NGINX. When charset, source_charset, charset_map\u00a0and proxy_pass\u00a0with disabled buffering (\"off\") directives are configured, an unauthenticated attacker can send crafted requests and cause a heap-based buffer over-read in the worker process, resulting in a limited disclosure of memory or a denial of service by forcing the process to restart."], "mitigation": {"lang": "en:us", "value": "To mitigate this vulnerability, enable proxy buffering (the default configuration)."}, "name": "CVE-2026-42934", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "nginx", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "nginx:1.24/nginx", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "nginx", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "nginx:1.24/nginx", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "nginx:1.26/nginx", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Not affected", "package_name": "nginx", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:insights_proxy:1", "fix_state": "Fix deferred", "package_name": "insights-proxy/insights-proxy-container-rhel9", "product_name": "Red Hat Lightspeed proxy 1"}], "public_date": "2026-05-13T14:12:44Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-42934\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-42934\nhttps://my.f5.com/manage/s/article/K000161028"], "statement": "To exploit this vulnerability, the charset, source_charset, charset_map and proxy_pass directives must be configured with disabled buffering, limiting its exposure as this is not the default configuration. Also, configurations that do not recode a UTF-8 response through charset_map are not vulnerable. This issue allows an attacker to have limited control to disclose memory content from the worker process or cause a denial of service by forcing the process to restart, but it cannot cause a complete system denial of service. Due to these reasons, this flaw has been rated with a moderate severity.", "threat_severity": "Moderate"}

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