Vulnerability-Lookup

ubuntu-cve-2026-4271

Vulnerability from osv_ubuntu

Published

2026-03-17 12:16

Modified

2026-07-10 00:02

Summary

Details

A flaw was found in libsoup, a library for handling HTTP requests. This vulnerability, known as a Use-After-Free, occurs in the HTTP/2 server implementation. A remote attacker can exploit this by sending specially crafted HTTP/2 requests that cause authentication failures. This can lead to the application attempting to access memory that has already been freed, potentially causing application instability or crashes, resulting in a Denial of Service (DoS).

Severity

5.3 (Medium)


                    
                      CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

7.5 (High)


                    
                      CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-4271	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-4271	REPORT
	https://gitlab.gnome.org/GNOME/libsoup/-/issues/496	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "gir1.2-soup-3.0",
            "binary_version": "3.0.7-0ubuntu1+esm7"
          },
          {
            "binary_name": "libsoup-3.0-0",
            "binary_version": "3.0.7-0ubuntu1+esm7"
          },
          {
            "binary_name": "libsoup-3.0-common",
            "binary_version": "3.0.7-0ubuntu1+esm7"
          },
          {
            "binary_name": "libsoup-3.0-tests",
            "binary_version": "3.0.7-0ubuntu1+esm7"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:22.04:LTS",
        "name": "libsoup3",
        "purl": "pkg:deb/ubuntu/libsoup3@3.0.7-0ubuntu1+esm7?arch=source\u0026distro=esm-apps/jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.0.4-2",
        "3.0.4-3",
        "3.0.5-1",
        "3.0.7-0ubuntu1",
        "3.0.7-0ubuntu1+esm1",
        "3.0.7-0ubuntu1+esm2",
        "3.0.7-0ubuntu1+esm3",
        "3.0.7-0ubuntu1+esm4",
        "3.0.7-0ubuntu1+esm5",
        "3.0.7-0ubuntu1+esm6",
        "3.0.7-0ubuntu1+esm7"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "gir1.2-soup-3.0",
            "binary_version": "3.4.4-5ubuntu0.7"
          },
          {
            "binary_name": "libsoup-3.0-0",
            "binary_version": "3.4.4-5ubuntu0.7"
          },
          {
            "binary_name": "libsoup-3.0-common",
            "binary_version": "3.4.4-5ubuntu0.7"
          },
          {
            "binary_name": "libsoup-3.0-tests",
            "binary_version": "3.4.4-5ubuntu0.7"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "libsoup3",
        "purl": "pkg:deb/ubuntu/libsoup3@3.4.4-5ubuntu0.7?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.4.2-4",
        "3.4.4-1",
        "3.4.4-2",
        "3.4.4-4",
        "3.4.4-5",
        "3.4.4-5build1",
        "3.4.4-5build2",
        "3.4.4-5ubuntu0.1",
        "3.4.4-5ubuntu0.2",
        "3.4.4-5ubuntu0.3",
        "3.4.4-5ubuntu0.4",
        "3.4.4-5ubuntu0.5",
        "3.4.4-5ubuntu0.6",
        "3.4.4-5ubuntu0.7"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "gir1.2-soup-3.0",
            "binary_version": "3.6.5-4ubuntu0.2"
          },
          {
            "binary_name": "libsoup-3.0-0",
            "binary_version": "3.6.5-4ubuntu0.2"
          },
          {
            "binary_name": "libsoup-3.0-common",
            "binary_version": "3.6.5-4ubuntu0.2"
          },
          {
            "binary_name": "libsoup-3.0-tests",
            "binary_version": "3.6.5-4ubuntu0.2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "libsoup3",
        "purl": "pkg:deb/ubuntu/libsoup3@3.6.5-4ubuntu0.2?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.6.5-1",
        "3.6.5-1ubuntu1",
        "3.6.5-3",
        "3.6.5-4",
        "3.6.5-4ubuntu0.1",
        "3.6.5-4ubuntu0.2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "gir1.2-soup-3.0",
            "binary_version": "3.6.6-1"
          },
          {
            "binary_name": "libsoup-3.0-0",
            "binary_version": "3.6.6-1"
          },
          {
            "binary_name": "libsoup-3.0-common",
            "binary_version": "3.6.6-1"
          },
          {
            "binary_name": "libsoup-3.0-tests",
            "binary_version": "3.6.6-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "libsoup3",
        "purl": "pkg:deb/ubuntu/libsoup3@3.6.6-1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.6.5-4",
        "3.6.5-5",
        "3.6.5-6",
        "3.6.5-7",
        "3.6.5-9",
        "3.6.6-1"
      ]
    }
  ],
  "aliases": [],
  "details": "A flaw was found in libsoup, a library for handling HTTP requests. This vulnerability, known as a Use-After-Free, occurs in the HTTP/2 server implementation. A remote attacker can exploit this by sending specially crafted HTTP/2 requests that cause authentication failures. This can lead to the application attempting to access memory that has already been freed, potentially causing application instability or crashes, resulting in a Denial of Service (DoS).",
  "id": "UBUNTU-CVE-2026-4271",
  "modified": "2026-07-10T00:02:00Z",
  "published": "2026-03-17T12:16:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-4271"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-4271"
    },
    {
      "type": "REPORT",
      "url": "https://gitlab.gnome.org/GNOME/libsoup/-/issues/496"
    }
  ],
  "related": [],
  "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:L",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-4271"
  ]
}

CVE-2026-4271 (GCVE-0-2026-4271)

Vulnerability from cvelistv5 – Published: 2026-03-17 11:14 – Updated: 2026-05-19 21:30

Title

Libsoup: libsoup: denial of service via use-after-free in http/2 server

Summary

Severity

5.3 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

SSVC

Exploitation: poc Automatable: yes Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-416 - Use After Free

Assigner

redhat

References

6 references

URL	Tags
https://access.redhat.com/errata/RHSA-2026:15968	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:17482	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:19143	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/security/cve/CVE-2026-4271	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2448044	issue-trackingx_refsource_REDHAT
https://gitlab.gnome.org/GNOME/libsoup/-/issues/496

Impacted products

7 products

Vendor	Product	Version
Red Hat	Red Hat Enterprise Linux 10	Unaffected: 0:3.6.5-3.el10_1.11 , < * (rpm) cpe:/o:redhat:enterprise_linux:10.1
Red Hat	Red Hat Enterprise Linux 10	Unaffected: 0:3.6.5-3.el10_2.11 , < * (rpm) cpe:/o:redhat:enterprise_linux:10.2
Red Hat	Red Hat Enterprise Linux 10.0 Extended Update Support	Unaffected: 0:3.6.5-3.el10_0.15 , < * (rpm) cpe:/o:redhat:enterprise_linux_eus:10.0
Red Hat	Red Hat Enterprise Linux 6	cpe:/o:redhat:enterprise_linux:6
Red Hat	Red Hat Enterprise Linux 7	cpe:/o:redhat:enterprise_linux:7
Red Hat	Red Hat Enterprise Linux 8	cpe:/o:redhat:enterprise_linux:8
Red Hat	Red Hat Enterprise Linux 9	cpe:/o:redhat:enterprise_linux:9

Date Public

2026-03-16 00:00

Credits

Red Hat would like to thank fouzhe for reporting this issue.

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-4271",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-03-17T13:04:24.452812Z",
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          "cpes": [
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            "confidentialityImpact": "NONE",
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            "privilegesRequired": "NONE",
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            "x_refsource_REDHAT"
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      ],
      "title": "Libsoup: libsoup: denial of service via use-after-free in http/2 server",
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    "datePublished": "2026-03-17T11:14:21.284Z",
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}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.

Action not permitted

ubuntu-cve-2026-4271

Vulnerability from osv_ubuntu

CVE-2026-4271 (GCVE-0-2026-4271)

Tags

Sightings

Nomenclature