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rlsa-2026:22121
Vulnerability from osv_rocky
Published
2026-08-26 00:04
Modified
2026-09-04 00:12
Summary
Important: golang security update
Details

The golang packages provide the Go programming language compiler.

Security Fix(es):

  • net/mail: golang: net/mail: Denial of Service via pathological email address parsing (CVE-2026-42499)

  • cmd/go: golang: Go command (cmd/go): Integrity bypass due to checksum validation flaw via malicious module proxy (CVE-2026-42501)

  • html/template: golang: Go html/template: Cross-Site Scripting via improper URL escaping in meta tag content (CVE-2026-39823)

  • cmd/go: golang: Go 'go bug' command: Arbitrary file overwrite via symlink attack (CVE-2026-39819)

  • net/http/internal/http2: golang: golang.org/x/net: Go HTTP/2: Denial of Service via malformed SETTINGS_MAX_FRAME_SIZE frame (CVE-2026-33814)

  • net/mail: golang: Go net/mail: Denial of Service via crafted email inputs (CVE-2026-39820)

  • net: golang: Go net package: Denial of Service via long CNAME response in LookupCNAME (CVE-2026-33811)

  • net/http/httputil: golang: net/http/httputil: ReverseProxy forwards hidden query parameters, potentially bypassing security controls (CVE-2026-39825)

  • cmd/go: golang: Go tool pack: Arbitrary file write via malicious archive extraction (CVE-2026-39817)

  • html/template: golang: html/template: Cross-site scripting due to incorrect script tag escaping (CVE-2026-39826)

  • net: golang: Go net package: Denial of Service via NUL byte in Dial and LookupPort on Windows (CVE-2026-39836)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Credits
Rocky Enterprise Software Foundation
Red Hat
References
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "Rocky Linux:9",
        "name": "golang",
        "purl": "pkg:rpm/rocky-linux/golang?distro=rocky-linux-9\u0026epoch=0"
      },
      "ranges": [
        {
          "database_specific": {
            "yum_repository": "AppStream"
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0:1.26.3-1.el9_8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "credits": [
    {
      "name": "Rocky Enterprise Software Foundation"
    },
    {
      "name": "Red Hat"
    }
  ],
  "database_specific": {
    "license": "CC-BY-4.0",
    "license_url": "https://creativecommons.org/licenses/by/4.0/",
    "source_advisory": "RHSA-2026:22121"
  },
  "details": "The golang packages provide the Go programming language compiler.\n\nSecurity Fix(es):\n\n* net/mail: golang: net/mail: Denial of Service via pathological email address parsing (CVE-2026-42499)\n\n* cmd/go: golang: Go command (cmd/go): Integrity bypass due to checksum validation flaw via malicious module proxy (CVE-2026-42501)\n\n* html/template: golang: Go html/template: Cross-Site Scripting via improper URL escaping in meta tag content (CVE-2026-39823)\n\n* cmd/go: golang: Go \u0027go bug\u0027 command: Arbitrary file overwrite via symlink attack (CVE-2026-39819)\n\n* net/http/internal/http2: golang: golang.org/x/net: Go HTTP/2: Denial of Service via malformed SETTINGS_MAX_FRAME_SIZE frame (CVE-2026-33814)\n\n* net/mail: golang: Go net/mail: Denial of Service via crafted email inputs (CVE-2026-39820)\n\n* net: golang: Go net package: Denial of Service via long CNAME response in LookupCNAME (CVE-2026-33811)\n\n* net/http/httputil: golang: net/http/httputil: ReverseProxy forwards hidden query parameters, potentially bypassing security controls (CVE-2026-39825)\n\n* cmd/go: golang: Go tool pack: Arbitrary file write via malicious archive extraction (CVE-2026-39817)\n\n* html/template: golang: html/template: Cross-site scripting due to incorrect script tag escaping (CVE-2026-39826)\n\n* net: golang: Go net package: Denial of Service via NUL byte in Dial and LookupPort on Windows (CVE-2026-39836)\n\nFor more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.",
  "id": "RLSA-2026:22121",
  "modified": "2026-09-04T00:12:56.080611Z",
  "published": "2026-08-26T00:04:43.459433Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://errata.rockylinux.org/RLSA-2026:22121"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2467809"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2467810"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2467811"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2467813"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2467815"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2467820"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2467822"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2467823"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2467825"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2467826"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2467827"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:22121"
    }
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Important: golang security update",
  "upstream": [
    "CVE-2026-33811",
    "CVE-2026-33814",
    "CVE-2026-39817",
    "CVE-2026-39819",
    "CVE-2026-39820",
    "CVE-2026-39823",
    "CVE-2026-39825",
    "CVE-2026-39826",
    "CVE-2026-39836",
    "CVE-2026-42499",
    "CVE-2026-42501"
  ]
}



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