CVE-2024-40900: Linux kernel · cachefiles: remove requests from xarray during flushing requests
Source GCVE Database
Not known to be exploited · CVSS 7.8 High.
Data as of 29 Oct 2026, 22:52 UTC
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 12 Jul 2024
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
Description
In the Linux kernel, the following vulnerability has been resolved: cachefiles: remove requests from xarray during flushing requests Even with CACHEFILES_DEAD set, we can still read the requests, so in the following concurrency the request may be used after it has been freed: mount | daemon_thread1 | daemon_thread2 ------------------------------------------------------------ cachefiles_ondemand_init_object cachefiles_ondemand_send_req REQ_A = kzalloc(sizeof(*req) + data_len) wait_for_completion(&REQ_A->done) cachefiles_daemon_read cachefiles_ondemand_daemon_read // close dev fd cachefiles_flush_reqs complete(&REQ_A->done) kfree(REQ_A) xa_lock(&cache->reqs); cachefiles_ondemand_select_req req->msg.opcode != CACHEFILES_OP_READ // req use-after-free !!! xa_unlock(&cache->reqs); xa_destroy(&cache->reqs) Hence remove requests from cache->reqs when flushing them to avoid accessing freed requests.
References
- nvd.nist.gov/vuln/detail/CVE-2024-40900 (opens in a new tab)
- git.kernel.org/stable/c/0fc75c5940fa634d84e64c93bfc388e1274ed013 (opens in a new tab)
- git.kernel.org/stable/c/37e19cf86a520d65de1de9cb330415c332a40d19 (opens in a new tab)
- git.kernel.org/stable/c/50d0e55356ba5b84ffb51c42704126124257e598 (opens in a new tab)
- git.kernel.org/stable/c/9f13aacdd4ee9a7644b2a3c96d67113cd083c9c7 (opens in a new tab)
- lists.debian.org/debian-lts-announce/2025/01/msg00001.html (opens in a new tab)