RHSA-2026:27197

Vulnerability from csaf_redhat - Published: 2026-06-19 09:14 - Updated: 2026-09-11 14:12
Summary
Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update
Severity
Important
Notes
Topic: An update for Red Hat Hardened Images RPMs is now available.
Details: This update includes the following RPMs: nginx: * nginx-1.30.3-2.hum1 (aarch64, x86_64) * nginx-all-modules-1.30.3-2.hum1 (noarch) * nginx-core-1.30.3-2.hum1 (aarch64, x86_64) * nginx-filesystem-1.30.3-2.hum1 (noarch) * nginx-mod-devel-1.30.3-2.hum1 (aarch64, x86_64) * nginx-mod-http-geoip-1.30.3-2.hum1 (aarch64, x86_64) * nginx-mod-http-image-filter-1.30.3-2.hum1 (aarch64, x86_64) * nginx-mod-http-perl-1.30.3-2.hum1 (aarch64, x86_64) * nginx-mod-http-xslt-filter-1.30.3-2.hum1 (aarch64, x86_64) * nginx-mod-mail-1.30.3-2.hum1 (aarch64, x86_64) * nginx-mod-stream-1.30.3-2.hum1 (aarch64, x86_64) * nginx-mod-stream-geoip-1.30.3-2.hum1 (aarch64, x86_64) * nginx-1.30.3-2.hum1.src (src)
Terms of Use: This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original.
CVE-2026-42055

A flaw was found in NGINX. When NGINX is configured to proxy HTTP/2 traffic using the ngx_http_proxy_v2_module or ngx_http_grpc_module with specific settings, a remote, unauthenticated attacker can send specially crafted large headers. This can trigger a heap-based buffer overflow, leading to a restart of the NGINX worker process and a Denial of Service (DoS). Under certain conditions, such as when Address Space Layout Randomization (ASLR) is disabled or bypassed, this vulnerability could also allow for arbitrary code execution.

8.1 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE-131 - Incorrect Calculation of Buffer Size
Affected products
Product Identifier Version Remediation
Unresolved product id: Red Hat Hardened Images:nginx-main@aarch64 —
Vendor Fix fix
Workaround
Unresolved product id: Red Hat Hardened Images:nginx-main@noarch —
Vendor Fix fix
Workaround
Unresolved product id: Red Hat Hardened Images:nginx-main@src —
Vendor Fix fix
Workaround
Unresolved product id: Red Hat Hardened Images:nginx-main@x86_64 —
Vendor Fix fix
Workaround
Threats
Impact Important
CVE-2026-48142

A flaw was found in NGINX. Remote, unauthenticated attackers can exploit a vulnerability in the `ngx_http_charset_module` when specific charset configurations are present. This can lead to a heap buffer over-read, potentially causing limited disclosure of memory or a denial of service by restarting the NGINX worker process.

4.8 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
CWE-125 - Out-of-bounds Read
Affected products
Fixed 4 products, the same list as for CVE-2026-42055
Threats
Impact Moderate
References
To clipboard 

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            "Red Hat Hardened Images:nginx-main@x86_64"
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          "details": "To mitigate this issue, avoid configuring NGINX with both `source_charset utf-8;` and an additional `charset` directive within the same location block in the `ngx_http_charset_module`. If these directives are not essential for your NGINX deployment, removing one or both will prevent the vulnerability from being exploited. After modifying the NGINX configuration, reload the NGINX service using `systemctl reload nginx`. This action may temporarily interrupt active connections.",
          "product_ids": [
            "Red Hat Hardened Images:nginx-main@aarch64",
            "Red Hat Hardened Images:nginx-main@noarch",
            "Red Hat Hardened Images:nginx-main@src",
            "Red Hat Hardened Images:nginx-main@x86_64"
          ]
        }
      ],
      "scores": [
        {
          "cvss_v3": {
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            "attackVector": "NETWORK",
            "availabilityImpact": "LOW",
            "baseScore": 4.8,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L",
            "version": "3.1"
          },
          "products": [
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            "Red Hat Hardened Images:nginx-main@noarch",
            "Red Hat Hardened Images:nginx-main@src",
            "Red Hat Hardened Images:nginx-main@x86_64"
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        }
      ],
      "threats": [
        {
          "category": "impact",
          "details": "Moderate"
        }
      ],
      "title": "nginx: NGINX: Memory disclosure or denial of service via ngx_http_charset_module heap buffer over-read"
    }
  ]
}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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Detection rules are retrieved from Rulezet.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.