CVE-2025-39994: media: tuner: xc5000: Fix use-after-free in xc5000_release
Vulnerability summary
CVE-2025-39994 is a high (CVSS 7.3) vulnerability in linux. EPSS estimates a 0.15% chance of exploitation in the next 30 days, higher than 4.6% of scored vulnerabilities.
Not severe (CVSS 7.3, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 48 · Related 41Timeline
- 15-10-2025PublishedVulnerability first disclosed.
- 15-10-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: media: tuner: xc5000: Fix use-after-free in xc5000_release The original code uses cancel_delayed_work() in xc5000_release(), which does not guarantee that the delayed work item timer_sleep has fully completed if it was already running. This leads to use-after-free scenarios where xc5000_release() may free the xc5000_priv while timer_sleep is still active and attempts to dereference the xc5000_priv. A typical race condition is illustrated below: CPU 0 (release thread) | CPU 1 (delayed work callback) xc5000_release() | xc5000_do_timer_sleep() cancel_delayed_work() | hybrid_tuner_release_state(priv) | kfree(priv) | | priv = container_of() // UAF Replace cancel_delayed_work() with cancel_delayed_work_sync() to ensure that the timer_sleep is properly canceled before the xc5000_priv memory is deallocated. A deadlock concern was considered: xc5000_release() is called in a process context and is not holding any locks that the timer_sleep work item might also need. Therefore, the use of the _sync() variant is safe here. This bug was initially identified through static analysis. [hverkuil: fix typo in Subject: tunner -> tuner]
CVSS metrics
4 scores · 4 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated7.3HighCVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated7.3HighCVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
- NVDNIST7.3HighCVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.15%
Chance of exploitation in the next 30 days
Percentile
5%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.15% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeNo weakness data has been published for this record.
Affected systems
Known conditions: local access, low-privilege account, user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu147 products
- linuxAll versions (No fix recorded) | < 5.15.0-170.180 | < 6.8.0-106.106 | < 6.17.0-6.6
- linux-allwinner-5.19All versions (No fix recorded)
- linux-awsAll versions (No fix recorded) | < 5.15.0-1100.107 | < 6.8.0-1050.53 | < 6.17.0-1003.3
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Debian1 product
- linux< 6.1.158-1 | < 6.12.57-1 | < 6.16.11-1
Linux1 product
- linux≥ f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8, < bc4ffd962ce16a154c44c68853b9d93f5b6fc4b8 | ≥ f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8, < e2f5eaafc0306a76fb1cb760aae804b065b8a341 | ≥ f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8, < 3f876cd47ed8bca1e28d68435845949f51f90703 | ≥ f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8, < df0303b4839520b84d9367c2fad65b13650a4d42 | ≥ f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8, < 71ed8b81a4906cb785966910f39cf7f5ad60a69e | ≥ f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8, < effb1c19583bca7022fa641a70766de45c6d41ac | ≥ f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8, < 9a00de20ed8ba90888479749b87bc1532cded4ce | ≥ f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8, < 4266f012806fc18e46da4a04d130df59a4946f93 | ≥ f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8, < 40b7a19f321e65789612ebaca966472055dab48c | 3.16
3 vendors · 149 products
