tpm: tpm2-sessions: wait for async KPP completion in tpm_buf_append_salt
Published Aug 15, 2026
8.4
HIGHCVSS 3.1
EPSS 0.20%
Description
tpm_buf_append_salt() in drivers/char/tpm/tpm2-sessions.c calls crypto_kpp_generate_public_key() and crypto_kpp_compute_shared_secret() without installing a completion callback, discards both return values, and immediately frees the kpp_request via kpp_request_free(). When the resolved ecdh-nist-p256 KPP backend is asynchronous (atmel-ecc, HPRE, keembay-ocs), either operation returns -EINPROGRESS and the deferred completion worker dereferences the freed request.
The path fires automatically from the hwrng_fillfn kernel thread via tpm_get_random -> tpm2_get_random -> tpm2_start_auth_session -> tpm_buf_append_salt on every entropy poll, without any userland action.
Install crypto_req_done as the completion callback, wrap both KPP operations in crypto_wait_req(), and propagate errors to the caller. The wait is a no-op for synchronous backends.
Affected products
-
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version
-
- Version 6.10StatusaffectedConstraints-
- Version 0StatusunaffectedConstraints<6.10
- Version 6.12.97StatusunaffectedConstraints<=6.12.*
- Version 6.18.40StatusunaffectedConstraints<=6.18.*
- Version 7.1.5StatusunaffectedConstraints<=7.1.*
- Version 7.2StatusunaffectedConstraints<=*
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
No data.
No data.
Red Hat Enterprise Linux 10
kernel
Affected
Red Hat Enterprise Linux 6
kernel
Not affected
Red Hat Enterprise Linux 7
kernel
Not affected
Red Hat Enterprise Linux 7
kernel-rt
Not affected
Red Hat Enterprise Linux 8
kernel
Not affected
Red Hat Enterprise Linux 8
kernel-rt
Not affected
Red Hat Enterprise Linux 9
kernel
Not affected
Red Hat Enterprise Linux 9
kernel-rt
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 10 | kernel | Affected | n/a |
| Red Hat Enterprise Linux 6 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 7 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 7 | kernel-rt | Not affected | n/a |
| Red Hat Enterprise Linux 8 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 8 | kernel-rt | Not affected | n/a |
| Red Hat Enterprise Linux 9 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 9 | kernel-rt | Not affected | n/a |
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
1 other source (Red Hat) ▾
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
No CVSS v3.0 score for this CVE.
No CVSS v2.0 score for this CVE.
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 3, 2026.
Score over time
Aug–Oct 2026- EPSS v5
Percentile over time
- EPSS v5
Table of values (2 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 3, 2026 | 0.20% (0.00196) | 8.37th | v5 (v2026.06.15) |
| Aug 15, 2026 | 0.20% (0.00200) | 10.14th | v5 (v2026.06.15) |
References (9)
- https://access.redhat.com/security/cve/CVE-2026-72151 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2516608 Issue Tracking
- https://git.kernel.org/stable/c/111e520efbe82b324bc42b1999b723c0619eea6d
- https://git.kernel.org/stable/c/493333f167926c7adab8e7563e21ad71d8af84fa
- https://git.kernel.org/stable/c/73851a7c43dfa52d2ed9415889b33daf85da0ed9
- https://git.kernel.org/stable/c/934d1cd40e2893bf7a041b54f6afd1c008d7a21c
- https://lore.kernel.org/linux-cve-announce/2026081534-CVE-2026-72151-db64@gregkh/T
- https://nvd.nist.gov/vuln/detail/CVE-2026-72151
- https://www.cve.org/CVERecord?id=CVE-2026-72151
Change history (0)
No recorded changes yet.