CVE-2026-70279
Microsoft Exchange Server Spoofing Vulnerability
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Microsoft Exchange Server Spoofing Vulnerability
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.
- Record
CVE-2026-70279- CVSS 3.1
- 9.3 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N/E:U/RL:O/RC:C - Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2026-100137
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.
- Record
EUVD-2026-100137- CVSS 3.1
- 9.3 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N/E:U/RL:O/RC:C - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-93hh-687q-gjhh
Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft...
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.
- Record
GHSA-93hh-687q-gjhh- CVSS 3.1
- 9.3 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-70279- CVSS 3.1
- 9.3 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-70279 is a critical vulnerability (CVSS 9.3) in Microsoft Exchange Server 2016 Cumulative Update 23, published October 13, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.29%, the 70th percentile. No source names a fixed version.