CVE-2022-49256: watch_queue: Actually free the watch
Vulnerability summary
CVE-2022-49256 is a medium (CVSS 5.5) vulnerability in linux. EPSS estimates a 0.26% chance of exploitation in the next 30 days, higher than 17.9% of scored vulnerabilities.
Not severe (CVSS 5.5, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 5 · Related 4Timeline
- 26-02-2025PublishedVulnerability first disclosed.
- 11-05-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: watch_queue: Actually free the watch free_watch() does everything barring actually freeing the watch object. Fix this by adding the missing kfree. kmemleak produces a report something like the following. Note that as an address can be seen in the first word, the watch would appear to have gone through call_rcu(). BUG: memory leak unreferenced object 0xffff88810ce4a200 (size 96): comm "syz-executor352", pid 3605, jiffies 4294947473 (age 13.720s) hex dump (first 32 bytes): e0 82 48 0d 81 88 ff ff 00 00 00 00 00 00 00 00 ..H............. 80 a2 e4 0c 81 88 ff ff 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff8214e6cc>] kmalloc include/linux/slab.h:581 [inline] [<ffffffff8214e6cc>] kzalloc include/linux/slab.h:714 [inline] [<ffffffff8214e6cc>] keyctl_watch_key+0xec/0x2e0 security/keys/keyctl.c:1800 [<ffffffff8214ec84>] __do_sys_keyctl+0x3c4/0x490 security/keys/keyctl.c:2016 [<ffffffff84493a25>] do_syscall_x64 arch/x86/entry/common.c:50 [inline] [<ffffffff84493a25>] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 [<ffffffff84600068>] entry_SYSCALL_64_after_hwframe+0x44/0xae
CVSS metrics
3 scores · 3 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.26%
Chance of exploitation in the next 30 days
Percentile
18%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.26% on 04-10-2026
Known exploited
Compare KEV catalogsNot in the CISA KEV catalog.
Not in the ENISA CNW catalog.
Not 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.
Ubuntu89 products
- linux< 5.15.0-37.39
- linux-allwinner-5.19All versions (No fix recorded)
- linux-aws< 5.15.0-1011.14
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ c73be61cede5882f9605a852414db559c0ebedfd, < 9d92be1a09fbb3dd65600dbfe7eedb40e7228e4b | ≥ c73be61cede5882f9605a852414db559c0ebedfd, < f69aecb49968e14196366bbe896eab0a904229f5 | ≥ c73be61cede5882f9605a852414db559c0ebedfd, < 7e8c9b0df07a77f0d072603b8ced2677e30e1893 | ≥ c73be61cede5882f9605a852414db559c0ebedfd, < 31824613a42aacdcbeb325bf07a1c8247a11ebe2 | ≥ c73be61cede5882f9605a852414db559c0ebedfd, < 3d8dcf278b1ee1eff1e90be848fa2237db4c07a7 | 5.8
- linux_kernel≥ 5.8, < 5.10.110 | ≥ 5.11, < 5.15.33 | ≥ 5.16, < 5.16.19 | ≥ 5.17, < 5.17.2
Debian1 product
- linux< 5.17.3-1
3 vendors · 92 products