CVE-2022-50638 — ext4: fix bug_on in __es_tree_search caused by bad boot loader inode
In the Linux kernel, the following vulnerability has been resolved: ext4: fix bug_on in __es_tree_search caused by bad boot loader inode We got a issue as fllows: ================================================================== kernel BUG at fs/ext4/extents_status.c:203! invalid opcode: 0000 [#1] PREEMPT SMP CPU: 1 PID: 945 Comm: cat Not tainted 6.0.0-next-20221007-dirty #349 RIP: 0010:ext4_es_end.isra.0+0x34/0x42 RSP: 0018:ffffc9000143b768 EFLAGS: 00010203 RAX: 0000000000000000 RBX: ffff8881769cd0b8 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8fc27cf7 RDI: 00000000ffffffff RBP: ffff8881769cd0bc R08: 0000000000000000 R09: ffffc9000143b5f8 R10: 0000000000000001 R11: 0000000000000001 R12: ffff8881769cd0a0 R13: ffff8881768e5668 R14: 00000000768e52f0 R15: 0000000000000000 FS: 00007f359f7f05c0(0000)GS:ffff88842fd00000(0000)knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f359f5a2000 CR3: 000000017130c000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __es_tree_search.isra.0+0x6d/0xf5 ext4_es_cache_extent+0xfa/0x230 ext4_cache_extents+0xd2/0x110 ext4_find_extent+0x5d5/0x8c0 ext4_ext_map_blocks+0x9c/0x1d30 ext4_map_blocks+0x431/0xa50 ext4_mpage_readpages+0x48e/0xe40 ext4_readahead+0x47/0x50 read_pages+0x82/0x530 page_cache_ra_unbounded+0x199/0x2a0 do_page_cache_ra+0x47/0x70 page_cache_ra_order+0x242/0x400 ondemand_readahead+0x1e8/0x4b0 page_cache_sync_ra+0xf4/0x110 filemap_get_pages+0x131/0xb20 filemap_read+0xda/0x4b0 generic_file_read_iter+0x13a/0x250 ext4_file_read_iter+0x59/0x1d0 vfs_read+0x28f/0x460 ksys_read+0x73/0x160 __x64_sys_read+0x1e/0x30 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x63/0xcd </TASK> ================================================================== In the above issue, ioctl invokes the swap_inode_boot_loader function to swap inode<5> and inode<12>. However, inode<5> contain incorrect imode and disordered extents, and i_nlink is set to 1. The extents check for inode in the ext4_iget function can be bypassed bacause 5 is EXT4_BOOT_LOADER_INO. While links_count is set to 1, the extents are not initialized in swap_inode_boot_loader. After the ioctl command is executed successfully, the extents are swapped to inode<12>, in this case, run the `cat` command to view inode<12>. And Bug_ON is triggered due to the incorrect extents. When the boot loader inode is not initialized, its imode can be one of the following: 1) the imode is a bad type, which is marked as bad_inode in ext4_iget and set to S_IFREG. 2) the imode is good type but not S_IFREG. 3) the imode is S_IFREG. The BUG_ON may be triggered by bypassing the check in cases 1 and 2. Therefore, when the boot loader inode is bad_inode or its imode is not S_IFREG, initialize the inode to avoid triggering the BUG.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+2
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux |
≥ 393d1d1d76933886d5e1ce603214c9987589c6d5 and < e76ede9d2c9e0af4573342b56d7cdbf757c18084≥ 393d1d1d76933886d5e1ce603214c9987589c6d5 and < a95ba369255ddcdc5e43d38bc5203537bdf3a518≥ 393d1d1d76933886d5e1ce603214c9987589c6d5 and < 5f8d36abd2059bf1bd016b17d1fe78d8613deddd≥ 393d1d1d76933886d5e1ce603214c9987589c6d5 and < 78e335fb573e6a85718c4c24d5a052718a99a9ed≥ 393d1d1d76933886d5e1ce603214c9987589c6d5 and < 71e99ec1315fe98d322b17b9a28f204aaf15ffee≥ 393d1d1d76933886d5e1ce603214c9987589c6d5 and < d480a49c15c465cb9a16db1379f4996e9b5bb9cc≥ 393d1d1d76933886d5e1ce603214c9987589c6d5 and < feec0ea94c5ef4aa118750284c8a921698733ef2≥ 393d1d1d76933886d5e1ce603214c9987589c6d5 and < a125c8806b7d3c3815b6f9f59d395b9d7527b0ef and 2 more≥ 393d1d1d76933886d5e1ce603214c9987589c6d5 and < 991ed014de0840c5dc405b679168924afb2952acversion 3.10 |
Vulnerable | CVE Program (cve.org) e CISA ADP |
EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.24%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Not enough vector or weakness data: use the affected application’s logs as a starting point.
Timeline
What happened to this CVE, newest first.
- 2026
- Record published
- Affected products added · linux/linux
- Source status changed · → Deferred
- Record created in this database
- 2025
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
9 on the record
- git.kernel.org/stable/c/e76ede9d2c9e0af4573342b56d7cdbf757c18084
- git.kernel.org/stable/c/d480a49c15c465cb9a16db1379f4996e9b5bb9cc
- git.kernel.org/stable/c/71e99ec1315fe98d322b17b9a28f204aaf15ffee
- git.kernel.org/stable/c/feec0ea94c5ef4aa118750284c8a921698733ef2
- git.kernel.org/stable/c/991ed014de0840c5dc405b679168924afb2952ac
- git.kernel.org/stable/c/78e335fb573e6a85718c4c24d5a052718a99a9ed
- git.kernel.org/stable/c/a125c8806b7d3c3815b6f9f59d395b9d7527b0ef
- git.kernel.org/stable/c/5f8d36abd2059bf1bd016b17d1fe78d8613deddd
- git.kernel.org/stable/c/a95ba369255ddcdc5e43d38bc5203537bdf3a518
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 12h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 12h
- Unknown CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 1d
- Unknown CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 1d
- Unknown CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 1d
- Unknown CVE-2026-98427 net/sched: codel: bound the dropping loop per dequeue call 1d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No CVSS score published by NVD, the CNA, CISA or GitHub so far.
- No fixed version, patch or mitigation documented.
- No CISA SSVC assessment.
- No CWE classification.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2022-50638 is "ext4: fix bug_on in __es_tree_search caused by bad boot loader inode", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.24% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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