CVE-2026-31580
HighIn the Linux kernel, the following vulnerability has been resolved: bcache: fix cached_dev.sb_bio use-after-free and crash In our production environment, we have received multiple crash reports regarding libceph, which have caught our attention: ``` [6888366.280350] Call Trace: [6888366.280452] blk_update_request+0x14e/0x370 [6888366.280561] blk_mq_end_request+0x1a/0x130 [6888366.280671] rbd_img_handle_request+0x1a0/0x1b0 [rbd] [6888366.280792] rbd_obj_handle_request+0x32/0x40 [rbd] [6888366.280903] __complete_request+0x22/0x70 [libceph] [6888366.281032] osd_dispatch+0x15e/0xb40 [libceph] [6888366.281164] ? inet_recvmsg+0x5b/0xd0 [6888366.281272] ? ceph_tcp_recvmsg+0x6f/0xa0 [libceph] [6888366.281405] ceph_con_process_message+0x79/0x140 [libceph] [6888366.281534] ceph_con_v1_try_read+0x5d7/0xf30 [libceph] [6888366.281661] ceph_con_workfn+0x329/0x680 [libceph] ``` After analyzing the coredump file, we found that the address of dc->sb_bio has been freed. We know that cached_dev is only freed when it is stopped. Since sb_bio is a part of struct cached_dev, rather than an alloc every time. If the device is stopped while writing to the superblock, the released address will be accessed at endio. This patch hopes to wait for sb_write to complete in cached_dev_free. It should be noted that we analyzed the cause of the problem, then tell all details to the QWEN and adopted the modifications it made.
CVSS 3.1 score
7.8
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness type
CWE-416CVE-2026-31580 is a Use After Free vulnerability
What is Use After Free?
The product references memory after it has been freed, which may cause it to crash, use unexpected values, or execute code. Learn more on MITRE CWE
Affected versions
Linux kernel versions
3.10
and later are affected. Fixed in
5.10.258,
5.15.209,
6.1.175,
6.6.136,
6.12.83,
6.18.24,
6.19.14,
7.0.1,
7.1-rc1
and their respective stable series.
References
The following references provide additional information about CVE-2026-31580 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
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PatchKernel patch commithttps://git.kernel.org/stable/c/2d6965581e164fa2ba3f7652ddae5535f6336576
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PatchKernel patch commithttps://git.kernel.org/stable/c/383f7fec0de8cee1cf7ae1f9d9f14044a61f10f9
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PatchKernel patch commithttps://git.kernel.org/stable/c/47fa09fe7f3e09df28a51cb2cbd8f5d2f7f6edc1
Frequently asked questions
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What is CVE-2026-31580?
CVE-2026-31580 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 , classified as an Use After Free flaw (CWE-416) . It affects Linux kernel versions from 3.10 onward and has been patched in 5.10.258, 5.15.209, 6.1.175 and others. CVE-2026-31580 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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What is the CVSS score for CVE-2026-31580?
CVE-2026-31580 has a CVSS score of 7.8 out of 10, rated High severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. -
Is there a patch available for CVE-2026-31580?
Yes — CVE-2026-31580 has been patched. Fixed versions include 5.10.258, 5.15.209, 6.1.175 and others. If you are running Linux kernel 3.10 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-31580 actively exploited?
No — CVE-2026-31580 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
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What is Use After Free (CWE-416)?
The product references memory after it has been freed, which may cause it to crash, use unexpected values, or execute code. View CWE-416 on MITRE CWE →