SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2026-57957

Papermark through 0.22.0 contains a cross-origin resource sharing (CORS) misconfiguration vulnerability that allows unauthenticated remote attackers to perform credentialed cross-origin requests by exploiting the TUS-based viewer upload endpoint…

LOW 2.3EPSS 0.44%

Does this matter?

Lower severity and a low EPSS score (0.44%). Track it; it rarely justifies an emergency change on its own.

Description

Papermark through 0.22.0 contains a cross-origin resource sharing (CORS) misconfiguration vulnerability that allows unauthenticated remote attackers to perform credentialed cross-origin requests by exploiting the TUS-based viewer upload endpoint reflecting arbitrary request Origins with Access-Control-Allow-Credentials set to true. Attackers can lure authenticated victims to malicious pages that silently issue credentialed cross-origin requests to upload arbitrary files into victim datarooms and read credentialed responses.

CVSS 4.0
2.3 LOWCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS
0.44% probability · 37th percentile
CISA KEV
Not listed
Weakness
CWE-942
Source
disclosure@vulncheck.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.