wifi: brcmfmac: fix use-after-free when rescheduling brcmf_btcoex_info work
In the Linux kernel, the following vulnerability has been resolved: wifi: brcmfmac: fix use-after-free when rescheduling brcmf_btcoex_info work The brcmf_btcoex_detach() only shuts down the btcoex timer, if the flag timer_on is false. However, the brcmf_btcoex_timerfunc(), which runs as timer handler, sets timer_on to false. This creates critical race conditions: 1.If brcmf_btcoex_detach() is called while brcmf_btcoex_timerfunc() is executing, it may observe timer_on as false and skip the call to timer_shutdown_sync(). 2.The brcmf_btcoex_timerfunc() may then reschedule the brcmf_btcoex_info worker after the cancel_work_sync() has been executed, resulting in use-after-free bugs. The use-after-free bugs occur in two distinct scenarios, depending on the timing of when the brcmf_btcoex_info struct is freed relative to the execution of its worker thread. Scenario 1: Freed before the worker is scheduled The brcmf_btcoex_info is deallocated before the worker is scheduled. A race condition can occur when schedule_work(&bt_local->work) is called after the target memory has been freed. The sequence of events is detailed below: CPU0 | CPU1 brcmf_btcoex_detach | brcmf_btcoex_timerfunc | bt_local->timer_on = false; if (cfg->btcoex->timer_on) | ... | cancel_work_sync(); | ... | kfree(cfg->btcoex); // FREE | | schedule_work(&bt_local->work); // USE Scenario 2: Freed after the worker is scheduled The brcmf_btcoex_info is freed after the worker has been scheduled but before or during its exec
CVE-2025-39863
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2025-39863
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "61730d4dfffc2cc9d3a49fad87633008105c18ba",
"lessThan": "c75600e69e66a751cc046cd9c407b942f298d852",
"versionType": "git"
},
{
"status": "affected",
"version": "61730d4dfffc2cc9d3a49fad87633008105c18ba",
"lessThan": "ae58f70bde0433f27ef4b388ab50634736607bf6",
"versionType": "git"
},
{
"status": "affected",
"version": "61730d4dfffc2cc9d3a49fad87633008105c18ba",
"lessThan": "f1150153c4e5940fe49ab51136343c5b4fe49d63",
"versionType": "git"
},
{
"status": "affected",
"version": "61730d4dfffc2cc9d3a49fad87633008105c18ba",
"lessThan": "3e789f8475f6c857c88de5c5bf4b24b11a477dd7",
"versionType": "git"
},
{
"status": "affected",
"version": "61730d4dfffc2cc9d3a49fad87633008105c18ba",
"lessThan": "2f6fbc8e04ca1d1d5c560be694199f847229c625",
"versionType": "git"
},
{
"status": "affected",
"version": "61730d4dfffc2cc9d3a49fad87633008105c18ba",
"lessThan": "9cb83d4be0b9b697eae93d321e0da999f9cdfcfc",
"versionType": "git"
}
],
"programFiles": [
"drivers/net/wireless/broadcom/brcm80211/brcmfmac/btcoex.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "3.10"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "3.10",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.15.210",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.167",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.105",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.46",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.16.6",
"versionType": "semver",
"lessThanOrEqual": "6.16.*"
},
{
"status": "unaffected",
"version": "6.17",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/net/wireless/broadcom/brcm80211/brcmfmac/btcoex.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2025-39863
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #27073 · Revision 1
- Added to Heist Feed
- Publisher date