CVE-2023-33404: An Unrestricted Upload vulnerability, due to insufficient validation on UploadControlled.cs file, in BlogEngin

Q: How do I fix CVE-2023-33404?

blogengine.net: upgrade to newer than 3.3.8.0. Exact commands for each OS are on this page.

Q: Is CVE-2023-33404 being exploited?

CVE-2023-33404 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2023-33404 affect?

CVE-2023-33404 affects blogengine.net. Severity is critical (CVSS 9.8). An Unrestricted Upload vulnerability, due to insufficient validation on UploadControlled.cs file, in BlogEngine.Net version 3.3.8.0 and earlier allows remote attackers to execute remote code.

Q: How urgent is CVE-2023-33404?

Priority 72/100. Critical severity; EPSS top 2%: very likely to be exploited; Public exploit reference; CISA SSVC: automatable with total technical impact; Remotely exploitable, no login, no user action

This week

CRITICAL 9.8REMOTEUPGRADE

CVE-2023-33404 is a critical-severity flaw (CVSS 9.8) affecting blogengine.net. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

An Unrestricted Upload vulnerability, due to insufficient validation on UploadControlled.cs file, in BlogEngine.Net version 3.3.8.0 and earlier allows remote attackers to execute remote code.

Why this priority

Critical severity
EPSS top 2%: very likely to be exploited
Public exploit reference
CISA SSVC: automatable with total technical impact
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	9.8 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	25.8% (top 2%)
CISA exploited list	No
Weakness	CWE-434
Published	2023-06-26
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: blogengine

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2023-06-26 20:15 UTCPublished CVE record published
2026-06-17 06:01 UTCUpdated Record last modified

blogengine blogengine.net UPGRADE

Affected: <= 3.3.8.0

Fixed in: newer than 3.3.8.0

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy blogengine.net || rpm -q blogengine.net || blogengine.net --version

2. UPGRADE to newer than 3.3.8.0 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade blogengine.net

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade blogengine.net

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Exact fixes by distribution

Fedora 46 · borgmatic · FIXED · 2.2.0-1.fc46 · FEDORA-2026-041229e71b · source

sudo dnf upgrade --advisory=FEDORA-2026-041229e71b

Fedora ELN · pie · FIXED · 1.5.4-1.eln159 · FEDORA-2026-a2c0261d3a · source

sudo dnf upgrade --advisory=FEDORA-2026-a2c0261d3a

Public exploits and detection

Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.

GitHub PoC: hacip/CVE-2023-33404 (0 stars)

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2023-33404?

blogengine.net: upgrade to newer than 3.3.8.0. Exact commands for each OS are on this page.

Is CVE-2023-33404 being exploited?

CVE-2023-33404 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2023-33404 affect?

CVE-2023-33404 affects blogengine.net. Severity is critical (CVSS 9.8). An Unrestricted Upload vulnerability, due to insufficient validation on UploadControlled.cs file, in BlogEngine.Net version 3.3.8.0 and earlier allows remote attackers to execute remote code.

How urgent is CVE-2023-33404?

Priority 72/100. Critical severity; EPSS top 2%: very likely to be exploited; Public exploit reference; CISA SSVC: automatable with total technical impact; Remotely exploitable, no login, no user action

Related CVEs

CVE-2023-33405 MEDIUM 6.1 UPGRADE Blogengine.net 3.3.8.0 and earlier is vulnerable to Open Redirect.
CVE-2023-22858 MEDIUM 5.3 DOWNGRADE An Improper Access Control vulnerability in BlogEngine.NET 3.3.8.0, allows unauthenticated visitors to access
CVE-2023-22857 HIGH 8.5 DOWNGRADE A stored Cross-site Scripting (XSS) vulnerability in BlogEngine.NET 3.3.8.0, allows injection of arbitrary Jav
CVE-2023-22856 HIGH 8.5 DOWNGRADE A stored Cross-site Scripting (XSS) vulnerability in BlogEngine.NET 3.3.8.0, allows injection of arbitrary Jav
CVE-2022-41418 HIGH 7.2 DOWNGRADE An issue in the component BlogEngine/BlogEngine.NET/AppCode/Api/UploadController.cs of BlogEngine.NET v3.3.8.0

References

← Back to latest CVEs