CVE-2026-53161
misc: fastrpc: fix use-after-free of fastrpc_user in workqueue context
Description
In the Linux kernel, the following vulnerability has been resolved: misc: fastrpc: fix use-after-free of fastrpc_user in workqueue context There is a race between fastrpc_device_release() and the workqueue that processes DSP responses. When the user closes the file descriptor, fastrpc_device_release() frees the fastrpc_user structure. Concurrently, an in-flight DSP invocation can complete and fastrpc_rpmsg_callback() schedules context cleanup via schedule_work(&ctx->put_work). If the workqueue runs fastrpc_context_free() in parallel with or after fastrpc_device_release() has freed the user structure, it dereferences the freed fastrpc_user. Depending on the state of the context at the time of the race, any one of the following accesses can be hit: 1. fastrpc_buf_free() calls fastrpc_ipa_to_dma_addr(buf->fl->cctx, ...) to strip the SID bits from the stored IOVA before passing the physical address to dma_free_coherent(). 2. fastrpc_free_map() reads map->fl->cctx->vmperms[0].vmid to reconstruct the source permission bitmask needed for the qcom_scm_assign_mem() call that returns memory from the DSP VM back to HLOS. 3. fastrpc_free_map() acquires map->fl->lock to safely remove the map node from the fl->maps list. The resulting use-after-free manifests as: pc : fastrpc_buf_free+0x38/0x80 [fastrpc] lr : fastrpc_context_free+0xa8/0x1b0 [fastrpc] fastrpc_context_free+0xa8/0x1b0 [fastrpc] fastrpc_context_put_wq+0x78/0xa0 [fastrpc] process_one_work+0x180/0x450 worker_thread+0x26c/0x388 Add kref-based reference counting to fastrpc_user. Have each invoke context take a reference on the user at allocation time and release it when the context is freed. Release the initial reference in fastrpc_device_release() at file close. Move the teardown of the user structure — freeing pending contexts, maps, mmaps, and the channel context reference — into the kref release callback fastrpc_user_free(), so that it runs only when the last reference is dropped, regardless of whether that happens at device close or after the final in-flight context completes.
INFO
Published Date :
June 25, 2026, 9:16 a.m.
Last Modified :
July 6, 2026, 4:42 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
Solution
- Add kref-based reference counting to fastrpc_user.
- Acquire user reference on context allocation.
- Release user reference on context free.
- Move teardown to kref release callback.
References to Advisories, Solutions, and Tools
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CVE-2026-53161.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-53161 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-53161
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-53161 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-53161 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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Initial Analysis by [email protected]
Jul. 06, 2026
Action Type Old Value New Value Added CWE CWE-416 Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.16 up to (excluding) 6.1.176 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.2 up to (excluding) 6.6.143 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.11 up to (excluding) 5.15.210 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.13 up to (excluding) 6.18.36 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.7 up to (excluding) 6.12.94 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.19 up to (excluding) 7.0.13 *cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc6:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc7:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.1 up to (excluding) 5.10.259 Added Reference Type kernel.org: https://git.kernel.org/stable/c/5278ccd357e0d7aeeb1e76c0f3e0e02894a9897c Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/c6e5c2be09f814377d7f1ce97370a5b7b3e02814 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/d42679eef34dd590b694ce3b666c5e2ba10cd4bf Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/df08fadcf0e5f3708365ec3b6d30b5aafd98bea1 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/e1e3a05efe5954d5bad01157d79429d39a67a7ae Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/e85eb5feca8e254905ffa6c57a3c99c89a674a0f Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/ecea4967c2bff92c2fafbc59893f711b39f7b152 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/fbe0947420eec18a84638d29468c2d563ce4e6a3 Types: Patch -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jun. 28, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jun. 25, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6cffd79504ce040f460831030d3069fa1c99bb71', 'lessThan': 'c6e5c2be09f814377d7f1ce97370a5b7b3e02814', 'versionType': 'git'}, {'status': 'affected', 'version': '6cffd79504ce040f460831030d3069fa1c99bb71', 'lessThan': 'e1e3a05efe5954d5bad01157d79429d39a67a7ae', 'versionType': 'git'}, {'status': 'affected', 'version': '6cffd79504ce040f460831030d3069fa1c99bb71', 'lessThan': 'd42679eef34dd590b694ce3b666c5e2ba10cd4bf', 'versionType': 'git'}, {'status': 'affected', 'version': '6cffd79504ce040f460831030d3069fa1c99bb71', 'lessThan': 'df08fadcf0e5f3708365ec3b6d30b5aafd98bea1', 'versionType': 'git'}, {'status': 'affected', 'version': '6cffd79504ce040f460831030d3069fa1c99bb71', 'lessThan': 'ecea4967c2bff92c2fafbc59893f711b39f7b152', 'versionType': 'git'}, {'status': 'affected', 'version': '6cffd79504ce040f460831030d3069fa1c99bb71', 'lessThan': '5278ccd357e0d7aeeb1e76c0f3e0e02894a9897c', 'versionType': 'git'}, {'status': 'affected', 'version': '6cffd79504ce040f460831030d3069fa1c99bb71', 'lessThan': 'fbe0947420eec18a84638d29468c2d563ce4e6a3', 'versionType': 'git'}, {'status': 'affected', 'version': '6cffd79504ce040f460831030d3069fa1c99bb71', 'lessThan': 'e85eb5feca8e254905ffa6c57a3c99c89a674a0f', 'versionType': 'git'}], 'programFiles': ['drivers/misc/fastrpc.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '5.1'}, {'status': 'unaffected', 'version': '0', 'lessThan': '5.1', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.10.259', 'versionType': 'semver', 'lessThanOrEqual': '5.10.*'}, {'status': 'unaffected', 'version': '5.15.210', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.176', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.143', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.94', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.36', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.0.13', 'versionType': 'semver', 'lessThanOrEqual': '7.0.*'}, {'status': 'unaffected', 'version': '7.1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['drivers/misc/fastrpc.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: misc: fastrpc: fix use-after-free of fastrpc_user in workqueue context There is a race between fastrpc_device_release() and the workqueue that processes DSP responses. When the user closes the file descriptor, fastrpc_device_release() frees the fastrpc_user structure. Concurrently, an in-flight DSP invocation can complete and fastrpc_rpmsg_callback() schedules context cleanup via schedule_work(&ctx->put_work). If the workqueue runs fastrpc_context_free() in parallel with or after fastrpc_device_release() has freed the user structure, it dereferences the freed fastrpc_user. Depending on the state of the context at the time of the race, any one of the following accesses can be hit: 1. fastrpc_buf_free() calls fastrpc_ipa_to_dma_addr(buf->fl->cctx, ...) to strip the SID bits from the stored IOVA before passing the physical address to dma_free_coherent(). 2. fastrpc_free_map() reads map->fl->cctx->vmperms[0].vmid to reconstruct the source permission bitmask needed for the qcom_scm_assign_mem() call that returns memory from the DSP VM back to HLOS. 3. fastrpc_free_map() acquires map->fl->lock to safely remove the map node from the fl->maps list. The resulting use-after-free manifests as: pc : fastrpc_buf_free+0x38/0x80 [fastrpc] lr : fastrpc_context_free+0xa8/0x1b0 [fastrpc] fastrpc_context_free+0xa8/0x1b0 [fastrpc] fastrpc_context_put_wq+0x78/0xa0 [fastrpc] process_one_work+0x180/0x450 worker_thread+0x26c/0x388 Add kref-based reference counting to fastrpc_user. Have each invoke context take a reference on the user at allocation time and release it when the context is freed. Release the initial reference in fastrpc_device_release() at file close. Move the teardown of the user structure — freeing pending contexts, maps, mmaps, and the channel context reference — into the kref release callback fastrpc_user_free(), so that it runs only when the last reference is dropped, regardless of whether that happens at device close or after the final in-flight context completes. Added Reference https://git.kernel.org/stable/c/5278ccd357e0d7aeeb1e76c0f3e0e02894a9897c Added Reference https://git.kernel.org/stable/c/c6e5c2be09f814377d7f1ce97370a5b7b3e02814 Added Reference https://git.kernel.org/stable/c/d42679eef34dd590b694ce3b666c5e2ba10cd4bf Added Reference https://git.kernel.org/stable/c/df08fadcf0e5f3708365ec3b6d30b5aafd98bea1 Added Reference https://git.kernel.org/stable/c/e1e3a05efe5954d5bad01157d79429d39a67a7ae Added Reference https://git.kernel.org/stable/c/e85eb5feca8e254905ffa6c57a3c99c89a674a0f Added Reference https://git.kernel.org/stable/c/ecea4967c2bff92c2fafbc59893f711b39f7b152 Added Reference https://git.kernel.org/stable/c/fbe0947420eec18a84638d29468c2d563ce4e6a3