SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2026-45727

CloakBrowser is a tool to bypass bot detection tests.

HIGH 8.8EPSS 0.47%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.47%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

CloakBrowser is a tool to bypass bot detection tests. Prior to version 0.3.28, the cloakserve CDP multiplexer uses the user-supplied fingerprint query parameter directly as a filesystem path component when creating Chrome profile directories. An unauthenticated attacker who can reach the cloakserve port can supply a crafted fingerprint value containing path traversal sequences to resolve user_data_dir outside the configured data_dir. When Chrome fails to start or the process is cleaned up, shutil.rmtree() deletes the traversed path, resulting in arbitrary directory deletion. Additionally, cloakserve bound to 0.0.0.0 by default, making it network-exposed. This issue has been patched in version 0.3.28.

CVSS 4.0
8.8 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS
0.47% probability · 40th percentile
CISA KEV
Not listed
Weakness
CWE-22
Source
security-advisories@github.com

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