CVE-2026-61448

LOW
INFO Priority: 0.01 BB Relevance: 44/100
Published: 2026-07-11 Modified: 2026-10-24 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity

CVSS Vector Breakdown

AV: Network
AC: Low
PR: Low
UI: Passive
S: X
AT: Present
VC: None
VI: Low
VA: None

Description

Parse Server is affected by a stored cross-site scripting (XSS) vulnerability in versions >= 9.0.0, < 9.10.0-alpha.2 and <= 8.6.83. When an uploaded file's extension is not recognized by the mime package, Parse Server preserves the client-supplied Content-Type. A malformed Content-Type that is not a valid type/subtype media type (e.g., 'image', 'image/', or 'image//svg+xml') bypasses the fileUpload.fileExtensions blocklist and is stored unchanged. On storage adapters that persist and serve the uploaded Content-Type (such as Amazon S3, Google Cloud Storage, or Azure Blob Storage), a browser cannot parse the malformed value and falls back to MIME-sniffing; a file whose body begins with HTML is rendered as HTML, executing embedded script in the application's origin against other users who open the file URL. The default GridFS storage adapter is not affected. Fixed in 9.10.0-alpha.2 and 8.6.84.

Weakness Classification (1)

Bug Bounty Relevance

44 / 100
✓ Network accessible
✓ Low complexity

CVSS Score

2.1 / 10.0 v4.0
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:L/VA:N/SC:L/SI:L/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

EPSS — Exploitation Probability

0.41%
Raw Score 0.004150
Percentile 35.7%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00415
2026-10-28
0.00415

Intelligence Sources

nvd ref →