8.1

CVE-2026-55007: microsoft exchange_server Double Free

CVSS: 8.1v3.1HighAnalyzed
Published 08-09-2026Last modified 14-10-2026
Open JSON

Vulnerability summary

CVE-2026-55007 is a high (CVSS 8.1) Double Free vulnerability in microsoft exchange_server. EPSS estimates a 0.71% chance of exploitation in the next 30 days, higher than 52.6% of scored vulnerabilities.

Overall risk
33/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.1/10
010
High · v3.1 (CVE.org)
EPSS score
0.71%
0%100%
Low · -0.02 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 08-09-2026
    PublishedVulnerability first disclosed.
  2. 14-10-2026
    Last modifiedVulnerability information updated.

Description

Double free in Microsoft Exchange Server allows an unauthorized attacker to execute code over a network.

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.71%

Chance of exploitation in the next 30 days

Percentile

53%

Versus all other CVEs

30-day change

-0.02 pp

From 0.73% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.71%

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

Microsoft5 products

1 vendor · 5 products

References

1 links