Linux: Exposure of Sensitive Information to an Unauthorized Actor
CVE-2026-72103 is a high-severity exposure of sensitive information to an unauthorized actor vulnerability in Linux, with a CVSS 3.1 base score of 7.3 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions d3eb8451d529ea452740d1a2bc395a1d20c48133, 8ced1d242c34e342defcccdb00663354f212aae6, f00105be6a593920e9bc7949a069d4a116888851 as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.16% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Linux to d3eb8451d529ea452740d1a2bc395a1d20c48133 or 8ced1d242c34e342defcccdb00663354f212aae6 or f00105be6a593920e9bc7949a069d4a116888851 or 981ccd97f7153d310dfa92a534525bbaf46752c2, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | a28d893eb3270cf62c10dd8777af0d8452cdc072 up to, but not including, d3eb8451d529ea452740d1a2bc395a1d20c48133; a28d893eb3270cf62c10dd8777af0d8452cdc072 up to, but not including, 8ced1d242c34e342defcccdb00663354f212aae6; a28d893eb3270cf62c10dd8777af0d8452cdc072 up to, but not including, f00105be6a593920e9bc7949a069d4a116888851; a28d893eb3270cf62c10dd8777af0d8452cdc072 up to, but not including, 981ccd97f7153d310dfa92a534525bbaf46752c2; 6.9 | d3eb8451d529ea452740d1a2bc395a1d20c48133, 8ced1d242c34e342defcccdb00663354f212aae6, f00105be6a593920e9bc7949a069d4a116888851, 981ccd97f7153d310dfa92a534525bbaf46752c2 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- LowPerformance or availability is reduced.
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L. Scored by CNA.
Official description
In the Linux kernel, the following vulnerability has been resolved: dm: avoid leaking the caller's thread keyring via the table device file The refactoring in commit a28d893eb327 ("md: port block device access to file") accidentally causes the caller's thread keyring to be kept alive long beyond the caller's lifetime. As a result, "cryptsetup luksSuspend" silently fails to wipe the LUKS volume key from memory. In detail: "cryptsetup luksOpen" uses its supposedly ephemeral thread keyring to pass the volume key to the kernel. dm-crypt's crypt_set_keyring_key() copies the key material into its own crypt_config structure and then drops its own reference to the key in the keyring with key_put(). With this fix, restoring pre-v6.9 behavior, the copy in the thread keyring is then promptly garbage collected, such that exactly one copy of the volume key remains. This single copy is correctly wiped from memory on "cryptsetup luksSuspend". Without this fix, the thread keyring and the volume key in it remains. This second copy is only freed on "luksClose". "luksSuspend" neither knows about this copy nor has any way to remove it, so the key remains recoverable from RAM after a suspend that is documented to have wiped it. This fix should not introduce new security problems, as the code is anyway gated by CAP_SYS_ADMIN. The device-mapper core, not the calling task, is the legitimate owner of this long-lived file.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Exposure of Sensitive Information to an Unauthorized Actor
The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.
How developers prevent this class of flaw
- Compartmentalize the system to have safe areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.
More Exposure of Sensitive Information to an Unauthorized Actor vulnerabilities (CWE-200)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other references
Recent Exposure of Sensitive Information to an Unauthorized Actor vulnerabilities
- 7.5 High severity
- 7.5 High severity
- 9.1 Critical severity
- 8.6 High severity
- 7.5 High severity
- 8.6 High severity
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