Skip to content
Fencer Vulns
critical 9.6

CVE-2026-55008 in the critical feed json

Microsoft Exchange Server Spoofing Vulnerability

published 2026-07-14 3 mo ago modified 2026-11-01 7 d ago also EUVD-2026-44026

cvss
9.6
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.9%
EPSS 0.9% chance of exploitation in 30 days, percentile 58%
public exploits
0
none known

Summary

Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Exchange Server allows an unauthorized attacker to perform spoofing over a network.

Patch / fix

  • Microsoft Microsoft Exchange Server 2016 Cumulative Update 23 15.01.2507.071
  • Microsoft Microsoft Exchange Server 2019 Cumulative Update 14 15.02.1544.043
  • Microsoft Microsoft Exchange Server 2019 Cumulative Update 15 15.02.1748.048
  • Microsoft Microsoft Exchange Server Subscription Edition RTM 15.02.2562.045

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
3 mo ago

Exploit prediction

0.86% chance of exploitation in the next 30 days, higher than 58% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 9.6 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C
CNA 3.1 9.6 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

Affected products

  • Microsoft Microsoft Exchange Server 2016 Cumulative Update 23
  • Microsoft Microsoft Exchange Server 2019 Cumulative Update 14
  • Microsoft Microsoft Exchange Server 2019 Cumulative Update 15
  • Microsoft Microsoft Exchange Server Subscription Edition RTM

Classification

Weakness
  • CWE-79 Improper Neutralization of Input During Web Page Generation
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.