Vulnerability-Lookup

GHSA-5MC7-P6PJ-R3F5

Vulnerability from github – Published: 2026-01-21 00:31 – Updated: 2026-01-21 00:31

Details

User-controlled header names and values containing newlines can allow injecting HTTP headers.

Severity ?

5.9 (Medium)


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

Show details on source website

JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-0865"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-74"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-01-20T22:15:52Z",
    "severity": "MODERATE"
  },
  "details": "User-controlled header names and values containing newlines can allow injecting HTTP headers.",
  "id": "GHSA-5mc7-p6pj-r3f5",
  "modified": "2026-01-21T00:31:42Z",
  "published": "2026-01-21T00:31:42Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-0865"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/issues/143916"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/pull/143917"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/commit/22e4d55285cee52bc4dbe061324e5f30bd4dee58"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/commit/23e3c0ae867cca0130e441e776c9955b9027c510"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/commit/2f840249550e082dc351743f474ba56da10478d2"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/commit/4802b96a2cde58570c24c13ef3289490980961c5"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/commit/e4846a93ac07a8ae9aa18203af0dd13d6e7a6995"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/commit/f7fceed79ca1bceae8dbe5ba5bc8928564da7211"
    },
    {
      "type": "WEB",
      "url": "https://mail.python.org/archives/list/security-announce@python.org/thread/BJ6QPHNSHJTS3A7CFV6IBMCAP2DWRVNT"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:N/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-2026-0865 (GCVE-0-2026-0865)

Vulnerability from cvelistv5 – Published: 2026-01-20 21:26 – Updated: 2026-01-21 16:14

Title

wsgiref.headers.Headers allows header newline injection

Summary

User-controlled header names and values containing newlines can allow injecting HTTP headers.

Severity ?

5.9 (Medium)


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

CWE

CWE-74 - Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

Assigner

PSF

References

URL

Tags

	https://github.com/python/cpython/pull/143917	patch
	https://github.com/python/cpython/issues/143916	issue-tracking
	https://mail.python.org/archives/list/security-an…	vendor-advisory
	https://github.com/python/cpython/commit/22e4d552…	patch
	https://github.com/python/cpython/commit/23e3c0ae…	patch
	https://github.com/python/cpython/commit/4802b96a…	patch
	https://github.com/python/cpython/commit/f7fceed7…	patch
	https://github.com/python/cpython/commit/2f840249…	patch
	https://github.com/python/cpython/commit/e4846a93…	patch

Impacted products

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

Credits

Omar M. Hasan

Show details on NVD website

JSON

To clipboard

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  "containers": {
    "adp": [
      {
        "metrics": [
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            "other": {
              "content": {
                "id": "CVE-2026-0865",
                "options": [
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                    "Exploitation": "none"
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                  },
                  {
                    "Technical Impact": "partial"
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                "role": "CISA Coordinator",
                "timestamp": "2026-01-21T15:40:22.223517Z",
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        },
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    ],
    "cna": {
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          "vendor": "Python Software Foundation",
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      "metrics": [
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          "cvssV4_0": {
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            "Recovery": "NOT_DEFINED",
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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-5MC7-P6PJ-R3F5

CVE-2026-0865 (GCVE-0-2026-0865)

Tags

Sightings

Nomenclature