CVE-2026-23205: smb/client: fix memory leak in smb2_open_file()
Vulnerability summary
CVE-2026-23205 is a medium (CVSS 5.5) vulnerability in linux. EPSS estimates a 0.13% chance of exploitation in the next 30 days, higher than 2.8% 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 16 · Related 9Timeline
- 14-02-2026PublishedVulnerability first disclosed.
- 23-05-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: smb/client: fix memory leak in smb2_open_file() Reproducer: 1. server: directories are exported read-only 2. client: mount -t cifs //${server_ip}/export /mnt 3. client: dd if=/dev/zero of=/mnt/file bs=512 count=1000 oflag=direct 4. client: umount /mnt 5. client: sleep 1 6. client: modprobe -r cifs The error message is as follows: ============================================================================= BUG cifs_small_rq (Not tainted): Objects remaining on __kmem_cache_shutdown() ----------------------------------------------------------------------------- Object 0x00000000d47521be @offset=14336 ... WARNING: mm/slub.c:1251 at __kmem_cache_shutdown+0x34e/0x440, CPU#0: modprobe/1577 ... Call Trace: <TASK> kmem_cache_destroy+0x94/0x190 cifs_destroy_request_bufs+0x3e/0x50 [cifs] cleanup_module+0x4e/0x540 [cifs] __se_sys_delete_module+0x278/0x400 __x64_sys_delete_module+0x5f/0x70 x64_sys_call+0x2299/0x2ff0 do_syscall_64+0x89/0x350 entry_SYSCALL_64_after_hwframe+0x76/0x7e ... kmem_cache_destroy cifs_small_rq: Slab cache still has objects when called from cifs_destroy_request_bufs+0x3e/0x50 [cifs] WARNING: mm/slab_common.c:532 at kmem_cache_destroy+0x16b/0x190, CPU#0: modprobe/1577
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
0.13%
Chance of exploitation in the next 30 days
Percentile
3%
Versus all other CVEs
30-day change
Increase +0.01 pp
From 0.12% 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.
Ubuntu129 products
- linux< 6.8.0-117.117 | All versions (No fix recorded)
- linux-allwinner-5.19All versions (No fix recorded)
- linux-aws< 6.8.0-1055.58 | All versions (No fix recorded)
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ 17e53a15e64b65623b8f2b1185d27d7b1cbf69ab, < 743f70406264348c0830f38409eb6c40a42fb2db | ≥ 18066188eb90cc0c798f3370a8078a79ddb73f70, < 3a6d6b332f92990958602c1e35ce0173e2dd62e9 | ≥ 6ebb9d54eccc8026b386e76eff69364d33373da5, < b64e3b5d8d759dd4333992e4ba4dadf9359952c8 | ≥ e255612b5ed9f179abe8196df7c2ba09dd227900, < 9ee608a64e37cea5b4b13e436c559dd0fb2ad1b5 | ≥ e255612b5ed9f179abe8196df7c2ba09dd227900, < e3a43633023e3cacaca60d4b8972d084a2b06236 | bcd15f06c7e8904116cfb06526bcc189b86aff85 | ≥ 6.1.141, < 6.1.163 | ≥ 6.6.93, < 6.6.124 | ≥ 6.12.31, < 6.12.70 | ≥ 6.14.9, < 6.15 | 6.15
- linux_kernel≥ 6.1.141, < 6.1.163 | ≥ 6.6.93, < 6.6.124 | ≥ 6.12.31, < 6.12.70 | ≥ 6.14.9, < 6.18.10 | 6.19:rc1 | 6.19:rc2 | 6.19:rc3 | 6.19:rc4 | 6.19:rc5 | 6.19:rc6 | 6.19:rc7 | 6.19:rc8
Debian1 product
- linux< 6.1.164-1 | < 6.12.73-1 | < 6.18.10-1
3 vendors · 132 products
