- 7.5HighCVSS base score
- 0.42%Exploitation in 30 daysEPSS · top 63% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Improper verification of cryptographic signature in Microsoft Exchange Server allows an authorized attacker to elevate privileges over a network.
Timeline
ID reserved
By microsoft
- 35 days later
· 35 days later
Published
- 18 days later
· 18 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| microsoftCNA (assigner) | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C |
| NVDNVD · Analyzed | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.42% · top 63% of all CVEs (9 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.
Affected products
Microsoft · Microsoft Exchange Server 2016 Cumulative Update 23
- affected 15.01.0.0 – < 15.01.2507.077
Microsoft · Microsoft Exchange Server 2019 Cumulative Update 14
- affected 15.02.0.0 – < 15.02.1544.050
Microsoft · Microsoft Exchange Server 2019 Cumulative Update 15
- affected 15.02.0.0 – < 15.02.1748.055
Microsoft · Microsoft Exchange Server Subscription Edition RTM
- affected 15.02.0.0 – < 15.02.2562.056
References
1
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-100145 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-87696)Record last updated .