CVE-2020-26768
Formstone <=1.4.16 is vulnerable to a Reflected Cross-Site Scripting (XSS) vulnerability caused by improper validation of user supplied input in the upload-target.php and upload-chunked.php files.
Does this matter?
Lower severity and a low EPSS score (1.28%). Track it; it rarely justifies an emergency change on its own.
Description
Formstone <=1.4.16 is vulnerable to a Reflected Cross-Site Scripting (XSS) vulnerability caused by improper validation of user supplied input in the upload-target.php and upload-chunked.php files. A remote attacker could exploit this vulnerability using a specially crafted URL to execute a script in a victim's Web browser within the security context of the hosting Web site once the URL is clicked or visited. An attacker could use this vulnerability to steal the victim's cookie-based authentication credentials, force malware execution, user redirection and others.
- CVSS 3.1
- 6.1 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
- EPSS
- 1.28% probability · 70th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-79
- Affected
- formstone/formstone
- Source
- cve@mitre.org
EPSS 1.3% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://github.com/Formstone/Formstone/issues/286Third Party Advisory
- https://github.com/Formstone/Formstone/issues/286Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.