GHSA-w5fm-68j4-fpc4: File Browser has a DoS Vulnerability via Public Login API
Summary
Unchecked passwords maximums allow for an arbitrarily large password to be passed into the login API. This spikes CPU and memory, and after testing, crashes, heavily lags any container created, and has even made my docker daemon start to send errors with status code 500 even after the container was destroyed.
Details
When sending JSON in the body of the request to the route api/login, if a large password is sent, there is no checking on a maximum length password. This means that any length string can be sent to the server and it will be hashed. Specifically the function CheckPwd in users/password.go is called to hash and check to see if the user supplied password is valid, but there is no maximum length for the password checked in that function. Depending on how many concurrent requests are being made, there may be no logs about the failed login attempts.
PoC
Create a file with a large password using this command:
yes "thisisalongphraseithinksoyeahitisactuallyimsureitiswhatisthisisamouthwoahimcoolwheredidthiscomefromwowza" | head -n 10000000 > large-password.txt
This makes a file that's about a gigabyte. The n parameter in the head function can be adjusted to increase or decrease the file size. Afterwards, run the following script to make a filebrowser container:
docker run -v filebrowser_data:/srv -v filebrowser_database:/database -v filebrowser_config:/config -p 8080:80 filebrowser/filebrowser
After running the container, it is recommended to bring up some sort of performance dashboard on the container that is running to monitor CPU and memory usage. Afterwards, run the following Python script (make sure to install dependencies: pip install aiohttp asyncio ). The CONCURRENT_REQUESTS parameter controls the number of requests to be making at one time. The TOTAL_REQUESTS parameter controls the grand total number of requests sent to the targeted container. If one wants more severe results, turn it up. If one wants less severe results, turn it down. The s
Details
Original advisory: https://github.com/advisories/GHSA-w5fm-68j4-fpc4
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-540920.48% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 39% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-54092 | coverage & exploitation status | NVD · CVE.org |
More from GitHub Security Advisories
- mediumGHSA-xm43-3m56-w3wf: Ghost: Paid gift memberships obtainable at minimal cost via the donations feature2026-08-04
- mediumGHSA-chgm-3698-jm42: Ghost: Member existence leak via magic link sign-in response2026-08-04
- highGHSA-xpp7-93x6-v29m: XSS in Ghost's ActivityPub client2026-08-04
- mediumGHSA-7mpp-r37j-x5wh: Ghost: Session Fixation in Ghost Admin2026-08-04
- mediumGHSA-cjc9-q5gf-327p: Ghost: Theme Upload Path Traversal2026-08-04