4.6

CVE-2026-59563: zscaler zscaler-mcp-server

CVSS: 4.6v3.1MediumAwaiting analysis
Published 28-09-2026Last modified 28-09-2026

Vulnerability summary

CVE-2026-59563 is a medium (CVSS 4.6) vulnerability in zscaler zscaler-mcp-server. EPSS estimates a 0.13% chance of exploitation in the next 30 days, higher than 2.4% of scored vulnerabilities.

Overall risk
18/100
0100
Low · default modelHow is this calculated?
CVSS score
4.6/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.13%
0%100%
Low · Change unavailable
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 28-09-2026
    PublishedVulnerability first disclosed.
  2. 28-09-2026
    Last modifiedVulnerability information updated.

Description

Zscaler MCP Server versions 0.7.0 and 0.7.1 has an issue where HMAC confirmation tokens were not bound to the target resource identifier, allowing an MCP client or agent to replay a token generated for one resource to affect another resource of the same type. This issue is fixed in version 0.7.2.

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.13%

Chance of exploitation in the next 30 days

Percentile

2%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

29-09-202621-10-2026
EPSS score
0.13%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Zscaler1 product

1 vendor · 1 product

References

1 links