Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-68200— ALSA: timer: don't re-enter an instance callback that is still running

Quick assessment

Affected
Linux Linux
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Linux kernel是美国Linux基金会开源的一个操作系统内核。 Linux kernel 6.12版本存在安全漏洞，该漏洞源于用户空间定时器TRIGGER ioctl调用snd_timer_interrupt时未序列化，可能导致并发回调引发释放后重用，任何能打开/dev/snd/timer的用户均可利用。

CVSS 7.8 · High EPSS 0.17% · P6

Possible ATT&CK Techniques 1 AI

T1203 · Exploitation for Client Execution

Affected Version Matrix 10

VendorProduct Version RangeStatus
Linux Linux 37745918e0e7575bc40f38da93a99b9fa6406224< 996c24377eea4d4506b7c3ccbbf1e490440b5e0b affected
37745918e0e7575bc40f38da93a99b9fa6406224< 1395327a96614885552bae5fbb650e6dd182d49b affected
37745918e0e7575bc40f38da93a99b9fa6406224< c1078130a4cd7e738f4b73afe99b3e68cbfbf884 affected
37745918e0e7575bc40f38da93a99b9fa6406224< 70d28bfcd6224eed75986b3b987b997e59643fa4 affected
6.12 affected
< 6.12 unaffected
6.12.101≤ 6.12.* unaffected
6.18.42≤ 6.18.* unaffected
… +2 more rows
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-68200

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
ALSA: timer: don't re-enter an instance callback that is still running
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: ALSA: timer: don't re-enter an instance callback that is still running The userspace-driven timer (utimer) TRIGGER ioctl calls snd_timer_interrupt() directly with no serialization, so two threads triggering the same utimer can run snd_timer_interrupt() on one snd_timer concurrently. snd_timer_process_callbacks() drops timer->lock around each instance callback and marks the in-flight callback with the single SNDRV_TIMER_IFLG_CALLBACK bit; snd_timer_close_locked() waits on that bit to drain an in-flight callback before freeing the instance. The bit cannot represent two concurrent callbacks: when a second interrupt re-queues an instance whose callback is still running, both run at once, the first to finish clears the bit, and the close-path drain then frees the instance (and its callback_data) while the other callback is still live - a use-after-free reachable by any user able to open /dev/snd/timer, both via a user timer instance and via a sequencer queue timer bound to the utimer. snd_timer_interrupt() sets IFLG_CALLBACK before dropping timer->lock, so a concurrent interrupt already observes it under the lock. Skip re-queuing an instance (and its slaves) to the ack/sack list while its callback is in flight; the accumulated pticks are delivered on the next tick, so no event is lost.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
N/A
Source: CVE Program / CVE List V5
Vulnerability Title
Linux kernel 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Linux kernel是美国Linux基金会开源的一个操作系统内核。 Linux kernel 6.12版本存在安全漏洞，该漏洞源于用户空间定时器TRIGGER ioctl调用snd_timer_interrupt时未序列化，可能导致并发回调引发释放后重用，任何能打开/dev/snd/timer的用户均可利用。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
Linux Linux 37745918e0e7575bc40f38da93a99b9fa6406224 ~ 996c24377eea4d4506b7c3ccbbf1e490440b5e0b -
Linux Linux 6.12 -

II. Public POCs for CVE-2026-68200

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-68200

请登录查看更多情报信息。

Patches & Fixes for CVE-2026-68200 (4)

Same Patch Batch · Linux · 2026-08-10 · 344 CVEs total

CVE-2026-68388 9.8 CRITICAL smb/client: handle overlapping allocated ranges in fallocate
CVE-2026-68136 9.8 CRITICAL net: gro: fix double aggregation of flush-marked skbs
CVE-2026-68137 9.8 CRITICAL net/x25: fix use-after-free in x25_kill_by_neigh()
CVE-2026-68144 9.8 CRITICAL phonet: pep: fix use-after-free in pep_get_sb()
CVE-2026-68127 9.8 CRITICAL ila: reload IPv6 header after pskb_may_pull in checksum adjust
CVE-2026-68154 9.8 CRITICAL libceph: reject zero bucket types in crush_decode
CVE-2026-68123 9.8 CRITICAL openvswitch: fix GSO userspace truncation underflow
CVE-2026-68156 9.8 CRITICAL libceph: refresh auth->authorizer_buf{,_len} after authorizer update
CVE-2026-68158 9.8 CRITICAL libceph: Fix multiplication overflow in decode_new_up_state_weight()
CVE-2026-68159 9.8 CRITICAL libceph: bound pg_{temp,upmap,upmap_items} length to CEPH_PG_MAX_SIZE
CVE-2026-68160 9.8 CRITICAL ceph: fix pre-auth out-of-bounds read on snaptrace in ceph_handle_caps()
CVE-2026-68161 9.8 CRITICAL sctp: close UDP tunnel sockets during netns teardown
CVE-2026-68117 9.8 CRITICAL tipc: clear sock->sk on the failed-insert path in tipc_sk_create()
CVE-2026-68170 9.8 CRITICAL mptcp: fix stale skb->sk reference on subflow close
CVE-2026-68385 9.8 CRITICAL s390/checksum: Fix csum_partial() without vector facility
CVE-2026-68381 9.8 CRITICAL ksmbd: pin conn during async oplock break notification
CVE-2026-68302 9.8 CRITICAL amt: re-read skb header pointers after every pull
CVE-2026-68426 9.8 CRITICAL xfrm: fix stale skb->prev after async crypto steals a GSO segment
CVE-2026-68300 9.8 CRITICAL sctp: auth: verify auth requirement when auth_chunk is NULL
CVE-2026-68124 9.6 CRITICAL mctp: serial: handle zero-length frames to prevent rx buffer overflow

Showing top 20 of 344 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

V. Comments for CVE-2026-68200

No comments yet

Leave a comment