OpenEMR before 8.4.0 Remote Code Execution via ESign LFI and fax upload
Affects OpenEMR before 8.4.0 when the fax module is set up with a vendor configured, not in a default install. Fixed in 8.4.0.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Exploited
- No known exploitation
- Fix
- Fixed in 8.4.0
- Who is exposed
- Specific setups only
Do first: Check whether your setup matches what the bug needs. Fax module enabled with a vendor configured (not a default install) Temporary files directory is known or at default (/tmp), so the traversal path can be built OpenEMR versions before 8.4.0
- Last modified
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 17/100 · provisional
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Specific setups only
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
OpenEMR before 8.4.0 contains a local file inclusion in the ESign router (library/ESign/Router.php), which passes the unsanitized module parameter into a require_once of '<module>/Controller.php', and the fax module's faxProcessUploads writes attacker-named files to a predictable temp path without extension checks. Authenticated attackers can upload a PHP file named Controller.php, then request interface/esign/index.php with a traversing module parameter to include it and execute arbitrary code.
cve.now Index
- Exploitation?/40Unknown. No CISA SSVC exploitation rating yet
- Exposure8/25Specific setups only, reachable over the network
- Reach?/20Unknown. No tracked technology or package matched
- Severity8.7/10CVSS 8.7
- No patch0/5No signal
What would change the score
- Would score about 67 if added to CISA KEV
- Would score about 62 if CISA's SSVC rates exploitation active
- Would score about 24 if CISA's SSVC rates it automatable
What to do
Check whether your setup matches what the bug needs.
Fax module enabled with a vendor configured (not a default install) Temporary files directory is known or at default (/tmp), so the traversal path can be built OpenEMR versions before 8.4.0Upgrade to a fixed version: 8.4.0.
Timeline
- CVE published
- First seen by cve.now
Affected versions
- openemr openemr
fixed in 8.4.0
Evidence 2
- Advisory
- Link
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-124467
Is CVE-2026-124467 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
What does this mean?
A flaw in the ESign and fax upload features allows a traversal path to be built through the temporary files directory, which leads to arbitrary PHP execution as the web-server user.Source: github.com, vulncheck.com
Which versions are affected by CVE-2026-124467?
openemr: before 8.4.0.Source: cve.now feed data
Am I affected, and how do I check?
OpenEMR versions before 8.4.0 are in scope, but only where the fax module is enabled with a vendor configured, and the temporary files directory is known or at the default /tmp. To check, look at the installed OpenEMR version and whether the fax module is set up with a vendor.Source: github.com, vulncheck.com
How do I fix CVE-2026-124467?
Upgrade to OpenEMR 8.4.0, the first fixed version.Source: github.com, vulncheck.com