fs: jfs: Fix UBSAN: array-index-out-of-bounds in dbAllocDmapLev
In the Linux kernel, the following vulnerability has been resolved: fs: jfs: Fix UBSAN: array-index-out-of-bounds in dbAllocDmapLev Syzkaller reported the following issue: UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dmap.c:1965:6 index -84 is out of range for type 's8[341]' (aka 'signed char[341]') CPU: 1 PID: 4995 Comm: syz-executor146 Not tainted 6.4.0-rc6-syzkaller-00037-gb6dad5178cea #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 ubsan_epilogue lib/ubsan.c:217 [inline] __ubsan_handle_out_of_bounds+0x11c/0x150 lib/ubsan.c:348 dbAllocDmapLev+0x3e5/0x430 fs/jfs/jfs_dmap.c:1965 dbAllocCtl+0x113/0x920 fs/jfs/jfs_dmap.c:1809 dbAllocAG+0x28f/0x10b0 fs/jfs/jfs_dmap.c:1350 dbAlloc+0x658/0xca0 fs/jfs/jfs_dmap.c:874 dtSplitUp fs/jfs/jfs_dtree.c:974 [inline] dtInsert+0xda7/0x6b00 fs/jfs/jfs_dtree.c:863 jfs_create+0x7b6/0xbb0 fs/jfs/namei.c:137 lookup_open fs/namei.c:3492 [inline] open_last_lookups fs/namei.c:3560 [inline] path_openat+0x13df/0x3170 fs/namei.c:3788 do_filp_open+0x234/0x490 fs/namei.c:3818 do_sys_openat2+0x13f/0x500 fs/open.c:1356 do_sys_open fs/open.c:1372 [inline] __do_sys_openat fs/open.c:1388 [inline] __se_sys_openat fs/open.c:1383 [inline] __x64_sys_openat+0x247/0x290 fs/open.c:1383 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f1f4e33f7e9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffc21129578 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1f4e33f7e9 RDX: 000000000000275a RSI: 0000000020000040 RDI: 00000000ffffff9c RBP: 00007f1f4e2ff080 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f1f4e2ff110 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> The bug occurs when the dbAllocDmapLev()function attempts to access dp->tree.stree[leafidx + LEAFIND] while the leafidx value is negative. To rectify this, the patch introduces a safeguard within the dbAllocDmapLev() function. A check has been added to verify if leafidx is negative. If it is, the function immediately returns an I/O error, preventing any further execution that could potentially cause harm. Tested via syzbot.
- Published
- Oct 1, 2025
- Updated
- Aug 5, 2026
- EPSS
- 0.2% · 7th percentile
- CWE
- CWE-129
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Report tools
Action score
31
Monitor
Low priority for now.
- CVSS
- 31 / 40 · 7.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.2%
CNA vs NVD score
- NVD
- 7.8
- CNA · Linux
- 7.8
- agree
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for the hundreds of thousands of vulnerabilities in the database; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpAffected systems
| Vendor | Product | CPE |
|---|---|---|
| linux | linux kernel | cpe:2.3:o:linux:linux_kernel |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- linux linux kernel2.6.12.1 and later · before 4.14.324
- linux linux kernel4.15 and later · before 4.19.293
- linux linux kernel4.20 and later · before 5.4.255
- linux linux kernel5.5 and later · before 5.10.192
- linux linux kernel5.11 and later · before 5.15.123
- linux linux kernel5.16 and later · before 6.1.42
- linux linux kernel6.2 and later · before 6.4.7
- linux linux kernel2.6.12
Versions reported by the vendor
Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.
Linux Linux
- 2.6.12affected
- 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and later · before 0d9e678a82915633b99603f744e7735d1a673d72affected · git
- 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and later · before 53b0a362aca2583729e8ca2936ca657ff3247d88affected · git
- 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and later · before 6e7d9d76e5654bcdd3cdb7c9441a8113428ecebbaffected · git
- 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and later · before 911b48eec45152822bccf45cd3563b48256b1520affected · git
- 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and later · before 39f6292d75959e8accac0b3e24090094ba0824e9affected · git
- 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and later · before bdf07ab1595b613b03f32dbb5cb379edfa1a7334affected · git
- 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and later · before f2af019091f904ca08b3572ab0111238ad6d17b3affected · git
- 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and later · before 4e302336d5ca1767a06beee7596a72d3bdc8d983affected · git
- before 2.6.12not affected · semver
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | linux | before 6.1.52-1 | 6.1.52-1 |
| Debian:13 | linux | before 6.4.11-1 | 6.4.11-1 |
Same product
linux: all recordsOther highest-scoring records for the same primary product.
- CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV89Now
- CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV85Now
- CVE-2016-5195Race condition in mm/gup.c in the Linux kernel 2.x through 4.x before 4.8.3 allows local users to gain privileges by leveraging incorrect haKEV83Now
- CVE-2019-13272In the Linux kernel before 5.1.17, ptrace_link in kernel/ptrace.c mishandles the recording of the credentials of a process that wants to creKEV77This week
- CVE-2013-6282The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the v6k and v7 ARM platforms do not validate certain addKEV77This week
- CVE-2013-2094The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9 uses an incorrect integer data type, which allows loKEV77This week
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| Linux Linux | 0d9e678a82915633b99603f744e7735d1a673d72 | Vendor (CNA) |
| Linux Linux | 39f6292d75959e8accac0b3e24090094ba0824e9 | Vendor (CNA) |
| Linux Linux | 4e302336d5ca1767a06beee7596a72d3bdc8d983 | Vendor (CNA) |
| Linux Linux | 53b0a362aca2583729e8ca2936ca657ff3247d88 | Vendor (CNA) |
| Linux Linux | 6e7d9d76e5654bcdd3cdb7c9441a8113428ecebb | Vendor (CNA) |
| Linux Linux | 911b48eec45152822bccf45cd3563b48256b1520 | Vendor (CNA) |
| Linux Linux | bdf07ab1595b613b03f32dbb5cb379edfa1a7334 | Vendor (CNA) |
| Linux Linux | f2af019091f904ca08b3572ab0111238ad6d17b3 | Vendor (CNA) |
| debian:linux | 6.1.52-1 · Debian:12 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2021-47548495 days apartethernet: hisilicon: hns: hns_dsaf_misc: fix a possible array overflow in hns_dsaf_ge_srst_by_port()39Monitor
- CVE-2026-23246168 days apartwifi: mac80211: bounds-check link_id in ieee80211_ml_reconfiguration35Monitor
- CVE-2023-5339513 days apartACPICA: Add AML_NO_OPERAND_RESOLVE flag to Timer31Monitor
- CVE-2023-5334014 days apartnet/mlx5: Collect command failures data only for known commands31Monitor
- CVE-2025-3982315 days apartKVM: x86: use array_index_nospec with indices that come from guest31Monitor
- CVE-2023-5319216 days apartvxlan: Fix nexthop hash size31Monitor
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Someone with local access to the system can trigger it.
- A low-privileged account is enough.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
CWE-129 · Improper Validation of Array IndexCVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
ATT&CK techniques
—
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- git.kernel.org/stable/c/0d9e678a82915633b99603f744e7735d1a673d72
- git.kernel.org/stable/c/39f6292d75959e8accac0b3e24090094ba0824e9
- git.kernel.org/stable/c/4e302336d5ca1767a06beee7596a72d3bdc8d983
- git.kernel.org/stable/c/53b0a362aca2583729e8ca2936ca657ff3247d88
- git.kernel.org/stable/c/6e7d9d76e5654bcdd3cdb7c9441a8113428ecebb
- git.kernel.org/stable/c/911b48eec45152822bccf45cd3563b48256b1520
- git.kernel.org/stable/c/bdf07ab1595b613b03f32dbb5cb379edfa1a7334
- git.kernel.org/stable/c/f2af019091f904ca08b3572ab0111238ad6d17b3
Vendor advisories and official records. Exploit/PoC links are deliberately left out.