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

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-89839— f2fs: use the mount idmap for the owner check in f2fs_xattr_advise_set()

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.

在 Linux 内核中，已修复以下漏洞： f2fs: 在 f2fs_xattr_advise_set() 中为所有者检查使用挂载 idmap 在允许设置 "system.advise" 扩展属性之前，调用 时使用了 ，而不是 VFS 传递给 处理程序的 idmap。 由于 f2fs 支持 idmapped 挂载，在这类挂载中，该检查会将调用者的 fsuid 与未映射的磁盘所有者进行比较，而非映射后的所有者：因此，真正的所有者可能被错误地以 拒绝，而一个不相关的调用者则可能被错误地允许通过。应改为使用处理程序传入的

AI Predicted 4.7 Difficulty: Moderate EPSS 0.20% · P9

Affected Version Matrix 12

VendorProduct Version RangeStatus
Linux Linux 01beba7957a26f9b7179127e8ad56bb5a0f56138< 4c0c610b480cfbc57528aa1acbd6be12ed2a6fb1 affected
01beba7957a26f9b7179127e8ad56bb5a0f56138< c3e2692c7a58e0bdb84bd658d827e89dcecea3ad affected
01beba7957a26f9b7179127e8ad56bb5a0f56138< 3b681229e9f8fb1dd29bc65983bf3c87779e4ca3 affected
01beba7957a26f9b7179127e8ad56bb5a0f56138< ab31e3b774f5d06b4489cef6c297b48c47c9dcbd affected
01beba7957a26f9b7179127e8ad56bb5a0f56138< a54ffce4637acb0db8e695188a6c7f99f14c3576 affected
6.3 affected
< 6.3 unaffected
6.6.157≤ 6.6.* unaffected
… +4 more rows
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-89839

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Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.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
f2fs: use the mount idmap for the owner check in f2fs_xattr_advise_set()
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: f2fs: use the mount idmap for the owner check in f2fs_xattr_advise_set() f2fs_xattr_advise_set() calls inode_owner_or_capable() with &nop_mnt_idmap before allowing the "system.advise" xattr to be set, instead of the idmap that the VFS passes to the ->set() handler. f2fs supports idmapped mounts, so on such a mount this checks the caller's fsuid against the unmapped on-disk owner rather than the mapped owner: the actual owner can be wrongly denied with -EPERM and an unrelated caller wrongly allowed. Pass the handler's idmap instead.
Source: CVE Program / CVE List V5
CVSS Information
N/A
Source: CVE Program / CVE List V5
Vulnerability Type
N/A
Source: CVE Program / CVE List V5

Affected Products

Vendor Product Affected Versions CPE Subscribe
Linux Linux 01beba7957a26f9b7179127e8ad56bb5a0f56138 ~ 4c0c610b480cfbc57528aa1acbd6be12ed2a6fb1 -
Linux Linux 6.3 -

II. Public POCs for CVE-2026-89839

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

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-89839

请登录查看更多情报信息。

Other References for CVE-2026-89839 (5)

Same Patch Batch · Linux · 2026-09-16 · 276 CVEs total

CVE-2026-90048 9.8 CRITICAL fs/ntfs3: fix slab-out-of-bounds write in ni_create_attr_list()
CVE-2026-90012 9.8 CRITICAL spi: Fix DMA mapping ownership on partial map failure
CVE-2026-89970 9.8 CRITICAL nvmet-auth: Synchronize timeout work during SQ teardown
CVE-2026-89857 9.8 CRITICAL scsi: qla2xxx: Hold qpair lock when sending NVMe LS reject
CVE-2026-89969 9.8 CRITICAL nvmet-tcp: fix out-of-bounds write when receiving an over-long PDU
CVE-2026-89847 9.8 CRITICAL scsi: qla2xxx: Avoid double completion in async IOCB timeout
CVE-2026-89972 9.8 CRITICAL nvme: add missing SRCU grace period in error path
CVE-2026-89990 9.8 CRITICAL ceph: lock mutex in ceph_mds_check_access()
CVE-2026-90036 9.8 CRITICAL NFSD: Prevent client use-after-free during blocked-lock reaping
CVE-2026-90038 9.8 CRITICAL NFSD: Prevent client use-after-free during export state revocation
CVE-2026-90037 9.8 CRITICAL NFSD: Prevent client use-after-free during close_lru reaping
CVE-2026-89788 9.8 CRITICAL ksmbd: fix tree connection use-after-free in smb2_tree_connect()
CVE-2026-89783 9.8 CRITICAL xfrm6: fix out-of-bounds write in xfrm6_input_addr() when secpath is full
CVE-2026-90042 9.8 CRITICAL ceph: properly decrypt filenames in vmalloc() buffers
CVE-2026-89778 9.8 CRITICAL isofs: fix out-of-bounds page array access on empty zisofs block
CVE-2026-89915 9.3 CRITICAL KVM: arm64: Remove VM-wide VNCR mapping counter
CVE-2026-90049 9.3 CRITICAL net: skbuff: don't skb_tx_error() the source skb in skb_zerocopy()
CVE-2026-89775 9.3 CRITICAL KVM: arm64: Handle negative S1 walk levels in VNCR TLB size evaluation
CVE-2026-89916 9.3 CRITICAL KVM: arm64: Make VNCR invalidation participate in MMU invalidation retry
CVE-2026-89930 9.3 CRITICAL KVM: nVMX: Service local TLB flushes on failed nested VM-Enter

Showing top 20 of 276 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

V. Comments for CVE-2026-89839

No comments yet

Leave a comment