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

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-43067— ext4: handle wraparound when searching for blocks for indirect mapped blocks

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基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞，该漏洞源于ext4在搜索间接映射块时未处理环绕问题，可能导致分配超出32位限制的块。

CVSS 9.8 · Critical EPSS 0.72% · P53

Possible ATT&CK Techniques 1 AI

T1190 · Exploit Public-Facing Application

Affected Version Matrix 13

VendorProduct Version RangeStatus
Linux Linux 9d89b9d55e25cb340c5b4b769876edc551b7a9ff< f89bba144938921a2249237ad04a0183ff3f8930 affected
1b0edd6022a3f44ce87fea9959a9310f4628fbea< 83170a05908b6cf2fb3235d3065bf613ff866f3c affected
9eea2f57d11b30049ff996ac3eff6e0dc8089e5f< 4bec4a498ce86314d470ae6144120461f2138c29 affected
34c803edc0b3365a42efcf9815acab63b4cf54e0< 12624c5b724a81e14e532972b40d863b0de3b7d1 affected
321ed8d559c951e71ad2d2d69a4cf0445644e865< 2a368ccddfc492a0aa951e2caef2985f20e96503 affected
4865c768b563deff1b6a6384e74a62f143427b42< bb81702370fad22c06ca12b6e1648754dbc37e0f affected
16fce6b6c0b247258c6c217fce5a48abf50f6964 affected
5.15.203< 5.16 affected
… +5 more rows
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-43067

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Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.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
ext4: handle wraparound when searching for blocks for indirect mapped blocks
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: ext4: handle wraparound when searching for blocks for indirect mapped blocks Commit 4865c768b563 ("ext4: always allocate blocks only from groups inode can use") restricts what blocks will be allocated for indirect block based files to block numbers that fit within 32-bit block numbers. However, when using a review bot running on the latest Gemini LLM to check this commit when backporting into an LTS based kernel, it raised this concern: If ac->ac_g_ex.fe_group is >= ngroups (for instance, if the goal group was populated via stream allocation from s_mb_last_groups), then start will be >= ngroups. Does this allow allocating blocks beyond the 32-bit limit for indirect block mapped files? The commit message mentions that ext4_mb_scan_groups_linear() takes care to not select unsupported groups. However, its loop uses group = *start, and the very first iteration will call ext4_mb_scan_group() with this unsupported group because next_linear_group() is only called at the end of the iteration. After reviewing the code paths involved and considering the LLM review, I determined that this can happen when there is a file system where some files/directories are extent-mapped and others are indirect-block mapped. To address this, add a safety clamp in ext4_mb_scan_groups().
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/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基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞，该漏洞源于ext4在搜索间接映射块时未处理环绕问题，可能导致分配超出32位限制的块。
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 9d89b9d55e25cb340c5b4b769876edc551b7a9ff ~ f89bba144938921a2249237ad04a0183ff3f8930 -
Linux Linux 6.1.167 ~ 6.1.168 -

II. Public POCs for CVE-2026-43067

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

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-43067

请登录查看更多情报信息。

Patches & Fixes for CVE-2026-43067 (6)

Same Patch Batch · Linux · 2026-05-05 · 15 CVEs total

CVE-2026-43071 9.1 CRITICAL dcache: Limit the minimal number of bucket to two
CVE-2026-43070 7.8 HIGH bpf: Reset register ID for BPF_END value tracking
CVE-2026-43063 7.8 HIGH xfs: don't irele after failing to iget in xfs_attri_recover_work
CVE-2026-43060 7.8 HIGH netfilter: nft_ct: drop pending enqueued packets on removal
CVE-2026-43062 7.1 HIGH Bluetooth: L2CAP: Fix type confusion in l2cap_ecred_reconf_rsp()
CVE-2026-43073 x86-64: rename misleadingly named '__copy_user_nocache()' function
CVE-2026-43072 drm/vc4: platform_get_irq_byname() returns an int
CVE-2026-43069 Bluetooth: hci_ll: Fix firmware leak on error path
CVE-2026-43068 ext4: avoid allocate block from corrupted group in ext4_mb_find_by_goal()
CVE-2026-43066 ext4: fix iloc.bh leak in ext4_fc_replay_inode() error paths
CVE-2026-43065 ext4: always drain queued discard work in ext4_mb_release()
CVE-2026-43064 dmaengine: idxd: Fix not releasing workqueue on .release()
CVE-2026-43061 serial: 8250: Fix TX deadlock when using DMA
CVE-2026-43059 Bluetooth: MGMT: Fix list corruption and UAF in command complete handlers

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

V. Comments for CVE-2026-43067

No comments yet

Leave a comment