CVE-2025-15282
Header injection via newlines in data URL mediatype
MEDIUM
6
CVSS Score
Published: January 20, 2026 at 09:35 PM UTC
Updated: June 17, 2026 at 08:37 AM UTC
1 product affected across 1 vendorPython
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Severity
MEDIUM6
Exploit prediction
EPSS 0.5%
SSVC
No known exploit
Description
User-controlled data URLs parsed by urllib.request.DataHandler allow injecting headers through newlines in the data URL mediatype.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
v < 3.10.203.11.0 ≤ v < 3.11.153.12.0 ≤ v < 3.12.133.13.0 ≤ v < 3.13.123.14.0 ≤ v < 3.14.33.15.0a1 ≤ v < 3.15.0a63.11.03.12.03.13.03.14.03.15.0a1
Affected range stops below 3.10.20, so it looks safe — our inference, not a vendor statement
Affected range stops below 3.11.15, so it looks safe — our inference, not a vendor statement
Affected range stops below 3.12.13, so it looks safe — our inference, not a vendor statement
Affected range stops below 3.13.12, so it looks safe — our inference, not a vendor statement
Affected range stops below 3.14.3, so it looks safe — our inference, not a vendor statement
Affected range stops below 3.15.0a6, so it looks safe — our inference, not a vendor statement
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
Patch and advisory references
- https://github.com/python/cpython/pull/143926
- https://mail.python.org/archives/list/[email protected]/thread/X66HL7SISGJT33J53OHXMZT4DFLMHVKF/
- https://github.com/python/cpython/commit/f25509e78e8be6ea73c811ac2b8c928c28841b9f
- https://github.com/python/cpython/commit/05356b1cc153108aaf27f3b72ce438af4aa218c0
- https://github.com/python/cpython/commit/34d76b00dabde81a793bd06dd8ecb057838c4b38
References (9)
Vendor Advisory
Source: cverecord
https://mail.python.org/archives/list/[email protected]/thread/X66HL7SISGJT33J53OHXMZT4DFLMHVKF/Patch
Source: cverecord
https://github.com/python/cpython/commit/f25509e78e8be6ea73c811ac2b8c928c28841b9fPatch
Source: cverecord
https://github.com/python/cpython/commit/05356b1cc153108aaf27f3b72ce438af4aa218c0Patch
Source: cverecord
https://github.com/python/cpython/commit/34d76b00dabde81a793bd06dd8ecb057838c4b38Patch
Source: cverecord
https://github.com/python/cpython/commit/3f396ca9d7bbe2a50ea6b8c9b27c0082884d9f80Patch
Source: cverecord
https://github.com/python/cpython/commit/4ed11d3cd288e6b90196a15c5a825a45d318fe47SSVC — Action Prioritization
SSVCNo known exploitNot automatablePartial impact
SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.
CVSS
6MEDIUMPSF
Vector?
Quick Info
StatusDEFERRED
CWE
CWE-93
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