Answer in brief
CVE-2026-43067 records a Critical severity (CVSS 9.8) vulnerability in ext4: handle wraparound when searching for blocks for indirect mapped blocks. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 9.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=9d89b9d55e25cb340c5b4b769876edc551b7a9ff <f89bba144938921a2249237ad04a0183ff3f8930 || >=1b0edd6022a3f44ce87fea9959a9310f4628fbea <83170a05908b6cf2fb3235d3065bf613ff866f3c || >=9eea2f57d11b30049ff996ac3eff6e0dc8089e5f <4bec4a498ce86314d470ae6144120461f2138c29 || >=34c803edc0b3365a42efcf9815acab63b4cf54e0 <12624c5b724a81e14e532972b40d863b0de3b7d1 || >=321ed8d559c951e71ad2d2d69a4cf0445644e865 <2a368ccddfc492a0aa951e2caef2985f20e96503 || >=4865c768b563deff1b6a6384e74a62f143427b42 <bb81702370fad22c06ca12b6e1648754dbc37e0f || 16fce6b6c0b247258c6c217fce5a48abf50f6964 || >=5.15.203 <5.16 | f89bba144938921a2249237ad04a0183ff3f8930, 83170a05908b6cf2fb3235d3065bf613ff866f3c, 4bec4a498ce86314d470ae6144120461f2138c29, 12624c5b724a81e14e532972b40d863b0de3b7d1, 2a368ccddfc492a0aa951e2caef2985f20e96503, bb81702370fad22c06ca12b6e1648754dbc37e0f, 5.16 |
| Linux/Linuxgeneric | >=6.1.167 <6.1.168 || >=6.6.130 <6.6.134 || >=6.12.77 <6.12.80 || >=6.18.14 <6.18.21 || >=6.19.4 <6.19.11 | 6.1.168, 6.6.134, 6.12.80, 6.18.21, 6.19.11 |
Published upstream
May 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 16, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 16, 2026
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().
Quoted source text, attributed separately from HOL analysis.