CVE-2026-40873

highpriority · track · 0EPSS 0.004 · 36 %ileEU

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.42% (36th) EPSS

CVSS 8.9 · high

Is it mine?

1 products

Check your exposure

Who says so?

2 sources

cnnvd · enisa_euvd

EPSS · scored 2026-10-27

mailcow: dockerized is an open source groupware/email suite based on docker. In versions prior to 2026-03b, the Quarantine details modal injects attachment filenames into HTML without escaping, allowing arbitrary HTML/JS execution. An attacker can deliver an email with a crafted attachment name so that when an admin views the quarantine item, JavaScript executes in their browser, taking over their account. Version 2026-03b fixes the vulnerability.

cvss

Technical severity, 0–10. One row per scoring source.

8.9

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6–8.9

v4.08.9highCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:Nsecondary · ENISA EU

v4.08.9highCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Xsecondary · security-advisories@github.com

v4.06mediumCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Xsecondary · CVSS-BT (t0sche)