ext4: fix BUG_ON() when directory entry has invalid rec_len
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 4 without a fix
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-617.
Summary
In the Linux kernel, the following vulnerability has been resolved: ext4: fix BUG_ON() when directory entry has invalid rec_len The rec_len field in the directory entry has to be a multiple of 4. A corrupted filesystem image can be used to hit a BUG() in ext4_rec_len_to_disk(), called from make_indexed_dir(). ------------[ cut here ]------------ kernel BUG at fs/ext4/ext4.h:2413! ... RIP: 0010:make_indexed_dir+0x53f/0x5f0 ... Call Trace: <TASK> ? add_dirent_to_buf+0x1b2/0x200 ext4_add_entry+0x36e/0x480 ext4_add_nondir+0x2b/0xc0 ext4_create+0x163/0x200 path_openat+0x635/0xe90 do_filp_open+0xb4/0x160 ? __create_object.isra.0+0x1de/0x3b0 ? _raw_spin_unlock+0x12/0x30 do_sys_openat2+0x91/0x150 __x64_sys_open+0x6c/0xa0 do_syscall_64+0x3c/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 The fix simply adds a call to ext4_check_dir_entry() to validate the directory entry, returning -EFSCORRUPTED if the entry is invalid.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 2.6.30 and later | 5.4.224, 5.10.154, 5.15.78, 6.0.8, 6.1 | Patch available | CNA |
- Linux VendorLinux Affected 2.6.30 and later Fixed in 5.4.224, 5.10.154, 5.15.78, 6.0.8, 6.1 Patch available CNA
CPE configurations NVD · 4
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | before 5.4.224; 5.5 to before 5.10.154; 5.11 to before 5.15.78; 5.16 to before 6.0.8 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.1:rc1:*:*:*:*:*:* | 6.1 rc1 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.1:rc2:*:*:*:*:*:* | 6.1 rc2 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.1:rc3:*:*:*:*:*:* | 6.1 rc3 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions before 5.4.224; 5.5 to before 5.10.154; 5.11 to before 5.15.78; 5.16 to before 6.0.8 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.1:rc1:*:*:*:*:*:* Versions 6.1 rc1 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.1:rc2:*:*:*:*:*:* Versions 6.1 rc2 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.1:rc3:*:*:*:*:*:* Versions 6.1 rc3 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 5.4.224, 5.10.154, 5.15.78, 6.0.8, 6.1
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 8 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
Not affected: 1 product
- Red Hat Enterprise Linux 10
Timeline
- 2026-10-02 Threatist record created from CVE-2022-49879
- 2026-10-03 Alias added: GHSA-82pr-9mpc-vgv5
- 2026-11-05 CISA SSVC decision points changed
References
Patch 5
- https://git.kernel.org/stable/c/2fa24d0274fbf913b56ee31f15bc01168669d909
- https://git.kernel.org/stable/c/156451a67b93986fb07c274ef6995ff40766c5ad
- https://git.kernel.org/stable/c/999cff2b6ce3b45c08abf793bf55534777421327
- https://git.kernel.org/stable/c/ce1ee2c8827fb6493e91acbd50f664cf2a972c3d
- https://git.kernel.org/stable/c/17a0bc9bd697f75cfdf9b378d5eb2d7409c91340
More Linux Kernel vulnerabilities
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- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
- TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
Sources
- CVE-2022-49879 · CVE Program
- CVE-2022-49879 · NVD
- FIRST EPSS
- GHSA-82pr-9mpc-vgv5 · GitHub Advisory Database · CC BY 4.0
- CVE-2022-49879 · Red Hat security data · CC BY 4.0
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