PatchTheCVECVE-2023-35373: Mono Authenticode Validation Spoofing Vulnerability
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Routine
MEDIUM 5.3WATCHLISTUPGRADE
CVE-2023-35373 is a medium-severity flaw (CVSS 5.3) affecting mono. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
Mono Authenticode Validation Spoofing Vulnerability
Why this priority
- On your watchlist
A fixed release or distro patch exists.
Risk facts
| CVSS score | 5.3 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | High |
| Privileges needed | Low |
| User interaction | None |
| EPSS exploit chance | 0.8% (top 43%) |
| CISA exploited list | No |
| Weakness | CWE-347 |
| Published | 2023-07-11 |
| Last modified | 2026-06-17 |
Publisher (CNA): Microsoft Corporation · Vendor: microsoft
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
microsoft mono UPGRADE
Affected: >= 6.12.0 and < 6.12.0.200
Fixed in: 6.12.0.200
Safe to downgrade to: a release before 6.12.0
1. Check installed version
apt-cache policy mono || rpm -q mono || mono --version
2. UPGRADE to 6.12.0.200 (Debian / Ubuntu)
sudo apt update && sudo apt install --only-upgrade mono
2. UPGRADE (RHEL / Amazon Linux / Fedora)
sudo dnf upgrade mono
Note
Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.
3. If no update is available yet, DOWNGRADE to a release before 6.12.0 (Debian / Ubuntu)
apt-cache madison mono
sudo apt install mono=<VERSION_BEFORE_6.12.0>
sudo apt-mark hold mono
3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list mono
sudo dnf downgrade mono-<VERSION_BEFORE_6.12.0>
sudo dnf versionlock add mono
Downgrade risk
Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.
After downgrade
Restart the service, and keep the package held until a fixed release ships.
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.
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-2023-35373?
mono: upgrade to 6.12.0.200. Exact commands for each OS are on this page.
Is CVE-2023-35373 being exploited?
CVE-2023-35373 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-2023-35373 affect?
CVE-2023-35373 affects mono. Severity is medium (CVSS 5.3). Mono Authenticode Validation Spoofing Vulnerability
How urgent is CVE-2023-35373?
Priority 38/100. On your watchlist
Related CVEs
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