CVE-2026-29964

HSC MailInspector v5.3.3-7 contains a Cross-Site Scripting (XSS) vulnerability in the /tap/tap.php endpoint due to improper neutralization of user-controlled input using alternate or obfuscated JavaScript syntax. The endpoint reflects unsanitized user input in HTTP responses without adequate output encoding, allowing a remote attacker to execute arbitrary JavaScript code in the context of a victim's browser.

Published: 2026-05-18 Last update: 2026-05-19 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-29964 is rated Low Risk (28.2/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.04%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-29964

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-19 — 0.04% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-29964

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.1 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 2.7 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2026-29964

GitHub Security Advisory for CVE-2026-29964

GHSA-pjr6-wxmx-75cg · Severity: medium — HSC MailInspector v5.3.3-7 contains a Cross-Site Scripting (XSS) vulnerability in the /tap/tap...

Affected software / configurations for CVE-2026-29964

Vendor Product Version Raw CPE
hsclabs mailinspector 5.3.3-7 cpe:2.3:a:hsclabs:mailinspector:5.3.3-7:*:*:*:*:*:*:*

References for CVE-2026-29964

cvelogic Threat Intelligence