CVE-2026-31543: crash_dump: don't log dm-crypt key bytes in read_key_from_user_keying
In the Linux kernel, the following vulnerability has been resolved:
crashdump: don't log dm-crypt key bytes in readkeyfromuserkeying
When debug logging is enabled, readkeyfromuserkeying() logs the first 8 bytes of the key payload and partially exposes the dm-crypt key. Stop logging any key bytes.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
linux/Kernelto a version that resolves this vulnerability.Fixed in 6.18.20 - Upgrade
Upgrade
linux/Kernelto a version that resolves this vulnerability.Fixed in 6.19.10 - Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 6.19.10-1 - Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 6.1.176-1Fixed in 6.1.190-1Fixed in 6.12.107-1Fixed in 6.12.116-1Fixed in 7.2.15-1Fixed in 7.3.4-1 - Configuration
Stop logging any key bytes when debug logging is enabled.
Linux kernel crash_dump/read_key_from_user_keying dm-crypt key-byte logging = disabled
Event History
Frequently Asked Questions
Which systems are exposed to this issue?
Systems using dm-crypt are exposed only when debug logging is enabled and the affected key-reading path is used. The issue concerns disclosure of the first 8 bytes of a key payload through logs.
What access would an attacker need to exploit this?
The provided vector indicates local access and low privileges are required, with no user interaction required. Exploitation depends on being able to cause or access the relevant debug log output.
Are default configurations affected?
The issue is triggered when debug logging is enabled. The provided information does not establish that debug logging is enabled by default.
What can be done before applying the fix?
Disable the relevant debug logging to prevent key bytes from being written to logs. Review and protect existing debug logs, since they may contain the first 8 bytes of dm-crypt key payloads.