Affects widely-used Microsoft 365 Copilot; could enable network privilege escalation.
CVE-2026-26137
SSRF in Microsoft 365 Copilot Business Chat allows privilege escalation.
Is CVE-2026-26137 being exploited?
Not confirmed. CVE-2026-26137 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.54% probability of exploitation in the next 30 days.
How severe is CVE-2026-26137?
CVE-2026-26137 is rated High with a CVSS score of 8.9. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-26137?
Yes. A fix has been recorded for CVE-2026-26137. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-26137 affect?
CVE-2026-26137 affects Microsoft 365 Copilot (Business Chat). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-26137?
Patch when available; restrict Copilot access; monitor for SSRF indicators
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Authorized attacker can use SSRF to escalate privileges across the network.
Patch when possible