Vulnerability-Lookup

GHSA-VF33-88PF-HWP3

Vulnerability from github – Published: 2026-03-16 18:32 – Updated: 2026-03-16 18:32

Details

The fix for CVE-2026-0672, which rejected control characters in http.cookies.Morsel, was incomplete. The Morsel.update(), |= operator, and unpickling paths were not patched, allowing control characters to bypass input validation. Additionally, BaseCookie.js_output() lacked the output validation applied to BaseCookie.output().

Severity ?

6.0 (Medium)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-3644"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-20"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-03-16T18:16:09Z",
    "severity": "MODERATE"
  },
  "details": "The fix for CVE-2026-0672, which rejected control characters in http.cookies.Morsel, was incomplete. The Morsel.update(), |= operator, and unpickling paths were not patched, allowing control characters to bypass input validation. Additionally, BaseCookie.js_output() lacked the output validation applied to BaseCookie.output().",
  "id": "GHSA-vf33-88pf-hwp3",
  "modified": "2026-03-16T18:32:04Z",
  "published": "2026-03-16T18:32:04Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-3644"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/issues/145599"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/pull/145600"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/commit/57e88c1cf95e1481b94ae57abe1010469d47a6b4"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/commit/62ceb396fcbe69da1ded3702de586f4072b590dd"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/commit/d16ecc6c3626f0e2cc8f08c309c83934e8a979dd"
    },
    {
      "type": "WEB",
      "url": "https://mail.python.org/archives/list/security-announce@python.org/thread/H6CADMBCDRFGWCMOXWUIHFJNV43GABJ7"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-3644 (GCVE-0-2026-3644)

Vulnerability from cvelistv5 – Published: 2026-03-16 17:37 – Updated: 2026-03-16 18:25

Title

Incomplete control character validation in http.cookies

Summary

Severity ?

6 (Medium)


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

CWE

CWE-20 - Improper Input Validation
CWE-116 - Improper Encoding or Escaping of Output

Assigner

PSF

References

URL

Tags

	https://mail.python.org/archives/list/security-an…	vendor-advisory
	https://github.com/python/cpython/commit/57e88c1c…	patch
	https://github.com/python/cpython/issues/145599	issue-tracking
	https://github.com/python/cpython/pull/145600	patch
	https://github.com/python/cpython/commit/62ceb396…	patch
	https://github.com/python/cpython/commit/d16ecc6c…	patch

Impacted products

	Vendor	Product	Version
	Python Software Foundation	CPython	Affected: 0 , < 3.15.0 (python)

Credits

Stan Ulbrych Stan Ulbrych Victor Stinner Seth Larson Vyom Yadav

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-3644",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-03-16T18:25:27.051552Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-20",
                "description": "CWE-20 Improper Input Validation",
                "lang": "en",
                "type": "CWE"
              }
            ]
          },
          {
            "descriptions": [
              {
                "cweId": "CWE-116",
                "description": "CWE-116 Improper Encoding or Escaping of Output",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-03-16T18:25:55.021Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "modules": [
            "http.cookies"
          ],
          "product": "CPython",
          "repo": "https://github.com/python/cpython",
          "vendor": "Python Software Foundation",
          "versions": [
            {
              "lessThan": "3.15.0",
              "status": "affected",
              "version": "0",
              "versionType": "python"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "coordinator",
          "value": "Stan Ulbrych"
        },
        {
          "lang": "en",
          "type": "remediation developer",
          "value": "Stan Ulbrych"
        },
        {
          "lang": "en",
          "type": "remediation reviewer",
          "value": "Victor Stinner"
        },
        {
          "lang": "en",
          "type": "remediation reviewer",
          "value": "Seth Larson"
        },
        {
          "lang": "en",
          "type": "reporter",
          "value": "Vyom Yadav"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
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            }
          ],
          "value": "The fix for CVE-2026-0672, which rejected control characters in http.cookies.Morsel, was incomplete. The Morsel.update(), |= operator, and unpickling paths were not patched, allowing control characters to bypass input validation. Additionally, BaseCookie.js_output() lacked the output validation applied to BaseCookie.output()."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "baseScore": 6,
            "baseSeverity": "MEDIUM",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "LOW",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "LOW",
            "vulnIntegrityImpact": "HIGH",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-03-16T17:45:23.093Z",
        "orgId": "28c92f92-d60d-412d-b760-e73465c3df22",
        "shortName": "PSF"
      },
      "references": [
        {
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://mail.python.org/archives/list/security-announce@python.org/thread/H6CADMBCDRFGWCMOXWUIHFJNV43GABJ7/"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/python/cpython/commit/57e88c1cf95e1481b94ae57abe1010469d47a6b4"
        },
        {
          "tags": [
            "issue-tracking"
          ],
          "url": "https://github.com/python/cpython/issues/145599"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/python/cpython/pull/145600"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/python/cpython/commit/62ceb396fcbe69da1ded3702de586f4072b590dd"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/python/cpython/commit/d16ecc6c3626f0e2cc8f08c309c83934e8a979dd"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "Incomplete control character validation in http.cookies",
      "x_generator": {
        "engine": "Vulnogram 1.0.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "28c92f92-d60d-412d-b760-e73465c3df22",
    "assignerShortName": "PSF",
    "cveId": "CVE-2026-3644",
    "datePublished": "2026-03-16T17:37:31.344Z",
    "dateReserved": "2026-03-06T16:13:09.289Z",
    "dateUpdated": "2026-03-16T18:25:55.021Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date

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.

Action not permitted

GHSA-VF33-88PF-HWP3

CVE-2026-3644 (GCVE-0-2026-3644)

Tags

Sightings

Nomenclature