Libsoup: incomplete fix for cve-2026-2443: range suffix overflow in libsoup soupserver

{
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "cveMetadata": {
    "cveId": "CVE-2026-12549",
    "assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
    "assignerShortName": "redhat",
    "dateUpdated": "2026-06-22T13:55:06.896Z",
    "dateReserved": "2026-06-17T18:40:22.117Z",
    "datePublished": "2026-06-22T13:55:06.896Z",
    "state": "PUBLISHED"
  },
  "containers": {
    "cna": {
      "providerMetadata": {
        "orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
        "shortName": "redhat",
        "dateUpdated": "2026-06-22T13:55:06.896Z"
      },
      "datePublic": "2024-04-24T00:00:00.000Z",
      "title": "Libsoup: incomplete fix for cve-2026-2443: range suffix overflow in libsoup soupserver",
      "descriptions": [
        {
          "lang": "en",
          "value": "The fix for CVE-2026-2443 was regressed by a subsequent rework commit that replaced specific overflow checks with a general signed comparison. When a client sends a Range request with a suffix length exceeding the content size, the resulting negative start value is not properly clamped, leading to malformed HTTP 206 responses and log flooding."
        }
      ],
      "affected": [
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 10",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup3",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:10"
          ],
          "defaultStatus": "affected"
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 6",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:6"
          ],
          "defaultStatus": "unknown"
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 7",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:7"
          ],
          "defaultStatus": "unknown"
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 8",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:8"
          ],
          "defaultStatus": "affected"
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 9",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:9"
          ],
          "defaultStatus": "affected"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "lang": "en",
              "description": "Buffer Access with Incorrect Length Value",
              "cweId": "CWE-805",
              "type": "CWE"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://access.redhat.com/security/cve/CVE-2026-12549",
          "tags": [
            "vdb-entry",
            "x_refsource_REDHAT"
          ]
        },
        {
          "url": "https://access.redhat.com/security/cve/cve-2026-0716",
          "name": "cve-2026-0716",
          "tags": [
            "technical-description",
            "x_refsource_REDHAT"
          ]
        },
        {
          "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2489999",
          "name": "RHBZ#2489999",
          "tags": [
            "issue-tracking",
            "x_refsource_REDHAT"
          ]
        },
        {
          "url": "https://gitlab.gnome.org/GNOME/libsoup/-/work_items/516"
        }
      ],
      "metrics": [
        {},
        {
          "format": "CVSS",
          "cvssV3_1": {
            "version": "3.1",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L",
            "attackVector": "NETWORK",
            "attackComplexity": "HIGH",
            "privilegesRequired": "NONE",
            "userInteraction": "NONE",
            "scope": "UNCHANGED",
            "confidentialityImpact": "LOW",
            "integrityImpact": "NONE",
            "availabilityImpact": "LOW",
            "baseScore": 4.8,
            "baseSeverity": "MEDIUM"
          }
        }
      ],
      "workarounds": [
        {
          "lang": "en",
          "value": "To mitigate this issue, applications utilizing libsoup's WebSocket support should ensure that the `max_incoming_payload_size` is explicitly set to a non-zero value. This prevents the library from processing WebSocket frames with an unset or zero maximum payload size, which can lead to out-of-bounds reads. Consult application-specific documentation for configuring libsoup parameters."
        }
      ],
      "timeline": [
        {
          "time": "2026-06-17T18:31:13.637Z",
          "lang": "en",
          "value": "Reported to Red Hat."
        },
        {
          "time": "2024-04-24T00:00:00.000Z",
          "lang": "en",
          "value": "Made public."
        }
      ]
    }
  }
}