Vulnerability-Lookup

OESA-2025-2250 (CVE-2025-57804)

Vulnerability from osv_openeuler – Published: 2025-09-12 11:09 – Updated: 2026-08-06 11:09 – Source website

Summary

python-h2 security update

Details

This repository contains a pure-Python implementation of a HTTP/2 protocol stack. It is written from the ground up to be embeddable in whatever program you choose to use, ensuring that you can speak HTTP/2 regardless of your programming paradigm.

Security Fix(es):

A vulnerability was found in python-hyper h2 up to 4.2.x (Programming Language Software) and classified as problematic.Using CWE to declare the problem leads to CWE-93. The product uses CRLF (carriage return line feeds) as a special element, e.g. to separate lines or records, but it does not neutralize or incorrectly neutralizes CRLF sequences from inputs.Impacted is integrity.Upgrading to version 4.3.0 eliminates this vulnerability. Applying the patch 035e9899f95e3709af098f578bfc3cd302298e3a is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.(CVE-2025-57804)

Severity

5.3 (Medium)


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

References

URL

Type

	https://www.openeuler.org/zh/security/security-bu…	ADVISORY
	https://nvd.nist.gov/vuln/detail/CVE-2025-57804	ADVISORY

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "noarch": [
          "python-h2-help-4.1.0-3.oe2403.noarch.rpm",
          "python3-h2-4.1.0-3.oe2403.noarch.rpm",
          "python-h2-help-4.1.0-3.oe2403sp1.noarch.rpm",
          "python3-h2-4.1.0-3.oe2403sp1.noarch.rpm",
          "python-h2-help-4.1.0-3.oe2403sp2.noarch.rpm",
          "python3-h2-4.1.0-3.oe2403sp2.noarch.rpm"
        ],
        "src": [
          "python-h2-4.1.0-3.oe2403.src.rpm",
          "python-h2-4.1.0-3.oe2403sp1.src.rpm",
          "python-h2-4.1.0-3.oe2403sp2.src.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:24.03-LTS",
        "name": "python-h2",
        "purl": "pkg:rpm/openEuler/python-h2\u0026distro=openEuler-24.03-LTS"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.1.0-3.oe2403sp2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "noarch": [
          "python-h2-help-4.1.0-3.oe2403sp1.noarch.rpm",
          "python3-h2-4.1.0-3.oe2403sp1.noarch.rpm"
        ],
        "src": [
          "python-h2-4.1.0-3.oe2403sp1.src.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:24.03-LTS-SP1",
        "name": "python-h2",
        "purl": "pkg:rpm/openEuler/python-h2\u0026distro=openEuler-24.03-LTS-SP1"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.1.0-3.oe2403sp1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "noarch": [
          "python-h2-help-4.1.0-3.oe2403sp2.noarch.rpm",
          "python3-h2-4.1.0-3.oe2403sp2.noarch.rpm"
        ],
        "src": [
          "python-h2-4.1.0-3.oe2403sp2.src.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:24.03-LTS-SP2",
        "name": "python-h2",
        "purl": "pkg:rpm/openEuler/python-h2\u0026distro=openEuler-24.03-LTS-SP2"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.1.0-3.oe2403sp2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "noarch": [
          "python-h2-help-4.0.0-2.oe2003sp4.noarch.rpm",
          "python3-h2-4.0.0-2.oe2003sp4.noarch.rpm"
        ],
        "src": [
          "python-h2-4.0.0-2.oe2003sp4.src.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:20.03-LTS-SP4",
        "name": "python-h2",
        "purl": "pkg:rpm/openEuler/python-h2\u0026distro=openEuler-20.03-LTS-SP4"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.0.0-2.oe2003sp4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "noarch": [
          "python-h2-help-4.0.0-3.oe2203sp3.noarch.rpm",
          "python3-h2-4.0.0-3.oe2203sp3.noarch.rpm"
        ],
        "src": [
          "python-h2-4.0.0-3.oe2203sp3.src.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:22.03-LTS-SP3",
        "name": "python-h2",
        "purl": "pkg:rpm/openEuler/python-h2\u0026distro=openEuler-22.03-LTS-SP3"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.0.0-3.oe2203sp3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "noarch": [
          "python-h2-help-4.0.0-3.oe2203sp4.noarch.rpm",
          "python3-h2-4.0.0-3.oe2203sp4.noarch.rpm"
        ],
        "src": [
          "python-h2-4.0.0-3.oe2203sp4.src.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:22.03-LTS-SP4",
        "name": "python-h2",
        "purl": "pkg:rpm/openEuler/python-h2\u0026distro=openEuler-22.03-LTS-SP4"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.0.0-3.oe2203sp4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "severity": "Medium"
  },
  "details": "This repository contains a pure-Python implementation of a HTTP/2 protocol stack. It is written from the ground up to be embeddable in whatever program you choose to use, ensuring that you can speak HTTP/2 regardless of your programming paradigm.\r\n\r\nSecurity Fix(es):\n\nA vulnerability was found in python-hyper h2 up to 4.2.x (Programming Language Software) and classified as problematic.Using CWE to declare the problem leads to CWE-93. The product uses CRLF (carriage return line feeds) as a special element, e.g. to separate lines or records, but it does not neutralize or incorrectly neutralizes CRLF sequences from inputs.Impacted is integrity.Upgrading to version 4.3.0 eliminates this vulnerability. Applying the patch 035e9899f95e3709af098f578bfc3cd302298e3a is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.(CVE-2025-57804)",
  "id": "OESA-2025-2250",
  "modified": "2026-08-06T11:09:19Z",
  "published": "2025-09-12T11:09:19Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2025-2250"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-57804"
    }
  ],
  "schema_version": "1.7.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "python-h2 security update",
  "upstream": [
    "CVE-2025-57804"
  ]
}

CVE-2025-57804 (GCVE-0-2025-57804)

Vulnerability from cvelistv5 – Published: 2025-08-25 21:04 – Updated: 2025-11-03 18:13

Title

h2 allows HTTP Request Smuggling due to illegal characters in headers

Summary

h2 is a pure-Python implementation of a HTTP/2 protocol stack. Prior to version 4.3.0, an HTTP/2 request splitting vulnerability allows attackers to perform request smuggling attacks by injecting CRLF characters into headers. This occurs when servers downgrade HTTP/2 requests to HTTP/1.1 without properly validating header names/values, enabling attackers to manipulate request boundaries and bypass security controls. This issue has been patched in version 4.3.0.

Severity

6.9 (Medium)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2025-08-26 19:14 UTC

CWE

CWE-93 - Improper Neutralization of CRLF Sequences ('CRLF Injection')

Assigner

GitHub_M mitre root

References

3 references

URL	Tags
https://github.com/python-hyper/h2/security/advis…	x_refsource_CONFIRM
https://github.com/python-hyper/h2/commit/035e989…	x_refsource_MISC
https://lists.debian.org/debian-lts-announce/2025…

Impacted products

1 product

Vendor	Product	Version
python-hyper	h2	Affected: < 4.3.0

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2025-57804",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-08-26T19:14:14.359281Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-08-26T19:14:49.643Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      },
      {
        "providerMetadata": {
          "dateUpdated": "2025-11-03T18:13:44.839Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "url": "https://lists.debian.org/debian-lts-announce/2025/09/msg00004.html"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "h2",
          "vendor": "python-hyper",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 4.3.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "h2 is a pure-Python implementation of a HTTP/2 protocol stack. Prior to version 4.3.0, an HTTP/2 request splitting vulnerability allows attackers to perform request smuggling attacks by injecting CRLF characters into headers. This occurs when servers downgrade HTTP/2 requests to HTTP/1.1 without properly validating header names/values, enabling attackers to manipulate request boundaries and bypass security controls. This issue has been patched in version 4.3.0."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 6.9,
            "baseSeverity": "MEDIUM",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "LOW",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-93",
              "description": "CWE-93: Improper Neutralization of CRLF Sequences (\u0027CRLF Injection\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2025-08-25T21:04:52.642Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
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          "tags": [
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          "url": "https://github.com/python-hyper/h2/commit/035e9899f95e3709af098f578bfc3cd302298e3a"
        }
      ],
      "source": {
        "advisory": "GHSA-847f-9342-265h",
        "discovery": "UNKNOWN"
      },
      "title": "h2 allows HTTP Request Smuggling due to illegal characters in headers"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
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    "cveId": "CVE-2025-57804",
    "datePublished": "2025-08-25T21:04:52.642Z",
    "dateReserved": "2025-08-20T14:30:35.009Z",
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    "state": "PUBLISHED"
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  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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.