madskristensen MiniBlog through 2018-05-18 allows remote attackers to execute arbitrary ASPX code via an IMG element with a data: URL, beca…

published 2019-06-14 7y ago modified 2026-06-17 4mo ago also EUVD-2019-19201

cvss: 7.2; version 3.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 2.2%; EPSS 2.2% chance of exploitation in 30 days, percentile 82%
public exploits: 0; none known

madskristensen MiniBlog through 2018-05-18 allows remote attackers to execute arbitrary ASPX code via an IMG element with a data: URL, because SaveFilesToDisk in app_code/handlers/PostHandler.cs writes a decoded base64 string to a file without validating the extension.

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Exploit prediction

2.16% chance of exploitation in the next 30 days, higher than 82% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

rastating.github.io https://rastating.github.io/miniblog-remote-code-execution/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.0	7.2	CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	6.5	AV:N/AC:L/Au:S/C:P/I:P/A:P

Classification

Weakness

CWE-434 Unrestricted Upload of File with Dangerous Type

References

rastating.github.io /miniblog-remote-code-execution/
exploit, third-party-advisory
github.com /madskristensen/MiniBlog/blob/1a7ae45ddba484e2c8f808e288e018748c9ddb57/Website/app_code/handlers/PostHandler.c
third-party-advisory

Sources

CVE List CVE-2019-9842
NVD CVE-2019-9842

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