In the Linux kernel, the following vulnerability has been resolved:
cifs: Fix use-after-free in rdata->read_into_pages()
When the network status is unstable, use-after-free may occur when
read data from the server.
BUG: KASAN: use-after-free in readpages_fill_pages+0x14c/0x7e0
Call Trace:
dump_stack_lvl+0x38/0x4c
print_report+0x16f/0x4a6
kasan_report+0xb7/0x130
readpages_fill_pages+0x14c/0x7e0
cifs_readv_receive+0x46d/0xa40
cifs_demultiplex_thread+0x121c/0x1490
kthread+0x16b/0x1a0
ret_from_fork+0x2c/0x50
Allocated by task 2535:
kasan_save_stack+0x22/0x50
kasan_set_track+0x25/0x30
__kasan_kmalloc+0x82/0x90
cifs_readdata_direct_alloc+0x2c/0x110
cifs_readdata_alloc+0x2d/0x60
cifs_readahead+0x393/0xfe0
read_pages+0x12f/0x470
page_cache_ra_unbounded+0x1b1/0x240
filemap_get_pages+0x1c8/0x9a0
filemap_read+0x1c0/0x540
cifs_strict_readv+0x21b/0x240
vfs_read+0x395/0x4b0
ksys_read+0xb8/0x150
do_syscall_64+0x3f/0x90
entry_SYSCALL_64_after_hwframe+0x72/0xdc
Freed by task 79:
kasan_save_stack+0x22/0x50
kasan_set_track+0x25/0x30
kasan_save_free_info+0x2e/0x50
__kasan_slab_free+0x10e/0x1a0
__kmem_cache_free+0x7a/0x1a0
cifs_readdata_release+0x49/0x60
process_one_work+0x46c/0x760
worker_thread+0x2a4/0x6f0
kthread+0x16b/0x1a0
ret_from_fork+0x2c/0x50
Last potentially related work creation:
kasan_save_stack+0x22/0x50
__kasan_record_aux_stack+0x95/0xb0
insert_work+0x2b/0x130
__queue_work+0x1fe/0x660
queue_work_on+0x4b/0x60
smb2_readv_callback+0x396/0x800
cifs_abort_connection+0x474/0x6a0
cifs_reconnect+0x5cb/0xa50
cifs_readv_from_socket.cold+0x22/0x6c
cifs_read_page_from_socket+0xc1/0x100
readpages_fill_pages.cold+0x2f/0x46
cifs_readv_receive+0x46d/0xa40
cifs_demultiplex_thread+0x121c/0x1490
kthread+0x16b/0x1a0
ret_from_fork+0x2c/0x50
The following function calls will cause UAF of the rdata pointer.
readpages_fill_pages
cifs_read_page_from_socket
cifs_readv_from_socket
cifs_reconnect
__cifs_reconnect
cifs_abort_connection
mid->callback() --> smb2_readv_callback
queue_work(&rdata->work) # if the worker completes first,
# the rdata is freed
cifs_readv_complete
kref_put
cifs_readdata_release
kfree(rdata)
return rdata->... # UAF in readpages_fill_pages()
Similarly, this problem also occurs in the uncache_fill_pages().
Fix this by adjusts the order of condition judgment in the return
statement.
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (7.8): severity, escalated by confirmed exploitation. This CVE's 7.8 is its impact severity (EG Severity), not escalated.
- EG Severity
- 7.8 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 0.7% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-27). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.
A fix is available. Apply it within your standard update timelines.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it