CVE-2023-52439: uio: Fix use-after-free in uio_open
Vulnerability summary
CVE-2023-52439 is a high (CVSS 7.8) Double Free vulnerability in linux. EPSS estimates a 0.30% chance of exploitation in the next 30 days, higher than 22.6% of scored vulnerabilities.
Not severe (CVSS 7.8, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 30 · Related 21Timeline
- 20-02-2024PublishedVulnerability first disclosed.
- 05-08-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: uio: Fix use-after-free in uio_open core-1 core-2 ------------------------------------------------------- uio_unregister_device uio_open idev = idr_find() device_unregister(&idev->dev) put_device(&idev->dev) uio_device_release get_device(&idev->dev) kfree(idev) uio_free_minor(minor) uio_release put_device(&idev->dev) kfree(idev) ------------------------------------------------------- In the core-1 uio_unregister_device(), the device_unregister will kfree idev when the idev->dev kobject ref is 1. But after core-1 device_unregister, put_device and before doing kfree, the core-2 may get_device. Then: 1. After core-1 kfree idev, the core-2 will do use-after-free for idev. 2. When core-2 do uio_release and put_device, the idev will be double freed. To address this issue, we can get idev atomic & inc idev reference with minor_lock.
CVSS metrics
4 scores · 4 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- NVDNIST7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.30%
Chance of exploitation in the next 30 days
Percentile
23%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.30% 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 causeAffected systems
Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu115 products
- linux< 4.15.0-225.237 | < 5.4.0-176.196 | < 5.15.0-102.112
- linux-allwinner-5.19All versions (No fix recorded)
- linux-aws< 4.15.0-1168.181 | < 5.4.0-1122.132 | < 5.15.0-1057.63
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ 57c5f4df0a5a0ee83df799991251e2ee93a5e4e9, < 3174e0f7de1ba392dc191625da83df02d695b60c | ≥ 57c5f4df0a5a0ee83df799991251e2ee93a5e4e9, < e93da893d52d82d57fc0db2ca566024e0f26ff50 | ≥ 57c5f4df0a5a0ee83df799991251e2ee93a5e4e9, < 5e0be1229ae199ebb90b33102f74a0f22d152570 | ≥ 57c5f4df0a5a0ee83df799991251e2ee93a5e4e9, < 5cf604ee538ed0c467abe3b4cda5308a6398f0f7 | ≥ 57c5f4df0a5a0ee83df799991251e2ee93a5e4e9, < 17a8519cb359c3b483fb5c7367efa9a8a508bdea | ≥ 57c5f4df0a5a0ee83df799991251e2ee93a5e4e9, < 35f102607054faafe78d2a6994b18d5d9d6e92ad | ≥ 57c5f4df0a5a0ee83df799991251e2ee93a5e4e9, < 913205930da6213305616ac539447702eaa85e41 | ≥ 57c5f4df0a5a0ee83df799991251e2ee93a5e4e9, < 0c9ae0b8605078eafc3bea053cc78791e97ba2e2 | 13af019c87f2d90e663742cb1a819834048842ae | ≥ 4.14.100, < 4.15 | 4.18
- linux_kernel> 4.18.0, < 4.19.306 | ≥ 4.20.0, < 5.4.268 | ≥ 5.5.0, < 5.10.209 | ≥ 5.11.0, < 5.15.148 | ≥ 5.16.0, < 6.1.74 | ≥ 6.2.0, < 6.6.13 | ≥ 6.7.0, < 6.7.1 | 4.18 | 4.18:rc5 | 4.18:rc6 | 4.18:rc7 | 4.18:rc8
Debian1 product
- linux< 6.1.76-1 | < 6.6.13-1
3 vendors · 118 products
