CVE Watch4 ago 2026

CVE-2024-57975

In the Linux kernel, the following vulnerability has been resolved: btrfs: do proper folio cleanup when run_delalloc_nocow() failed [BUG]

CVSS

7.8

Alto

EPSS

0.2%

p12

KEV

—

Exploit Today

0-100

Publicado: 27 feb 2025 · Última mod.: 4 ago 2026 · CWE-459

EPSS · 30d

0.2%EPSS · 30 días0.2%

2026-07-182026-08-15

Descripción técnica

In the Linux kernel, the following vulnerability has been resolved: btrfs: do proper folio cleanup when run_delalloc_nocow() failed [BUG] With CONFIG_DEBUG_VM set, test case generic/476 has some chance to crash with the following VM_BUG_ON_FOLIO(): BTRFS error (device dm-3): cow_file_range failed, start 1146880 end 1253375 len 106496 ret -28 BTRFS error (device dm-3): run_delalloc_nocow failed, start 1146880 end 1253375 len 106496 ret -28 page: refcount:4 mapcount:0 mapping:00000000592787cc index:0x12 pfn:0x10664 aops:btrfs_aops [btrfs] ino:101 dentry name(?):"f1774" flags: 0x2fffff80004028(uptodate|lru|private|node=0|zone=2|lastcpupid=0xfffff) page dumped because: VM_BUG_ON_FOLIO(!folio_test_locked(folio)) ------------[ cut here ]------------ kernel BUG at mm/page-writeback.c:2992! Internal error: Oops - BUG: 00000000f2000800 [#1] SMP CPU: 2 UID: 0 PID: 3943513 Comm: kworker/u24:15 Tainted: G OE 6.12.0-rc7-custom+ #87 Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022 Workqueue: events_unbound btrfs_async_reclaim_data_space [btrfs] pc : folio_clear_dirty_for_io+0x128/0x258 lr : folio_clear_dirty_for_io+0x128/0x258 Call trace: folio_clear_dirty_for_io+0x128/0x258 btrfs_folio_clamp_clear_dirty+0x80/0xd0 [btrfs] __process_folios_contig+0x154/0x268 [btrfs] extent_clear_unlock_delalloc+0x5c/0x80 [btrfs] run_delalloc_nocow+0x5f8/0x760 [btrfs] btrfs_run_delalloc_range+0xa8/0x220 [btrfs] writepage_delalloc+0x230/0x4c8 [btrfs] extent_writepage+0xb8/0x358 [btrfs] extent_write_cache_pages+0x21c/0x4e8 [btrfs] btrfs_writepages+0x94/0x150 [btrfs] do_writepages+0x74/0x190 filemap_fdatawrite_wbc+0x88/0xc8 start_delalloc_inodes+0x178/0x3a8 [btrfs] btrfs_start_delalloc_roots+0x174/0x280 [btrfs] shrink_delalloc+0x114/0x280 [btrfs] flush_space+0x250/0x2f8 [btrfs] btrfs_async_reclaim_data_space+0x180/0x228 [btrfs] process_one_work+0x164/0x408 worker_thread+0x25c/0x388 kthread+0x100/0x118 ret_from_fork+0x10/0x20 Code: 910a8021 a90363f7 a9046bf9 94012379 (d4210000) ---[ end trace 0000000000000000 ]--- [CAUSE] The first two lines of extra debug messages show the problem is caused by the error handling of run_delalloc_nocow(). E.g. we have the following dirtied range (4K blocksize 4K page size): 0 16K 32K |//////////////////////////////////////| | Pre-allocated | And the range [0, 16K) has a preallocated extent. - Enter run_delalloc_nocow() for range [0, 16K) Which found range [0, 16K) is preallocated, can do the proper NOCOW write. - Enter fallback_to_fow() for range [16K, 32K) Since the range [16K, 32K) is not backed by preallocated extent, we have to go COW. - cow_file_range() failed for range [16K, 32K) So cow_file_range() will do the clean up by clearing folio dirty, unlock the folios. Now the folios in range [16K, 32K) is unlocked. - Enter extent_clear_unlock_delalloc() from run_delalloc_nocow() Which is called with PAGE_START_WRITEBACK to start page writeback. But folios can only be marked writeback when it's properly locked, thus this triggered the VM_BUG_ON_FOLIO(). Furthermore there is another hidden but common bug that run_delalloc_nocow() is not clearing the folio dirty flags in its error handling path. This is the common bug shared between run_delalloc_nocow() and cow_file_range(). [FIX] - Clear folio dirty for range [@start, @cur_offset) Introduce a helper, cleanup_dirty_folios(), which will find and lock the folio in the range, clear the dirty flag and start/end the writeback, with the extra handling for the @locked_folio. - Introduce a helper to clear folio dirty, start and end writeback - Introduce a helper to record the last failed COW range end This is to trace which range we should skip, to avoid double unlocking. - Skip the failed COW range for the e ---truncated---

Referencias oficiales

CVEs relacionados

CVECVSSEPSSKEVRExplotTítuloVis.

CVE-2026-194747.5 ALT

—

——0@fastify/multipart is a multipart form-data parser for Fastify. In versions from 3.0.0 up to but not including 10.1.1, request.saveRequestFiles() can leave completed temporary files on disk when a client disconnects while the parser is advancing between multipart parts. The iterator rejection that occurs between parts falls outside the per-file cleanup path, so an earlier completed file is never removed. An unauthenticated client can repeat this to cause persistent, linear disk consumption, leading to denial of service. This is an incomplete-fix variant of CVE-2025-24033. The issue is fixed in @fastify/multipart 10.1.1. Users should upgrade to 10.1.1.1d CVE-2026-197304.2 MED

1.3%

——0The 'podman quadlet install --replace' command opens the existing destination file with O_CREATE|O_WRONLY but omits O_TRUNC. When the initial reflink copy attempt fails (common on non-reflink-capable filesystems including many RHEL default XFS configurations), the fallback in ReflinkOrCopy uses io.Copy which performs a non-truncating write. If the original Quadlet is larger than the new Quadlet, the file is not truncated and content from the original is preserved. The command completes with no warning. There is no risk of information leakage as the user already had access to the Quadlet in order to replace it, and in most cases, this would only lead to invalid Quadlet files. However, security-related options from the end of the old Quadlet could be included in the new Quadlet, and if the truncation resulted in a valid Quadlet file, this could result in undesirable behavior. For example, running podman quadlet install --replace to remove a single line from the end of a Quadlet - including security-sensitive content, like AddCapability - will fail, and the option will continue to be used. Further, with Volume Quadlets, this can include additional mounts which can cause content to be unintentionally exposed into containers. If, later, the image is updated then compromised content might be leaked to an attacker. The vulnerable code paths are in pkg/domain/infra/abi/quadlet.go (lines 338-360, O_CREATE|O_WRONLY without O_TRUNC) and vendor/go.podman.io/storage/pkg/fileutils/reflink_linux.go (lines 12-19, non-truncating io.Copy fallback).2d CVE-2026-20712—

2.1%

——1Incomplete cleanup in some UEFI firmware for some Intel(R) reference platforms within UEFI may allow an information disclosure. System software adversary with a privileged user combined with a low complexity attack may enable data exposure. This result may potentially occur via local access when attack requirements are present without special internal knowledge and requires no user interaction. The potential vulnerability may impact the confidentiality (none), integrity (none) and availability (none) of the vulnerable system, resulting in subsequent system confidentiality (high), integrity (none) and availability (none) impacts.4d CVE-2026-688095.5 MED

20.2%

——6Incomplete cleanup in Microsoft Office PowerPoint allows an unauthorized attacker to disclose information locally.2d CVE-2026-190194.8 MED

23.2%

——7A security flaw has been discovered in poco-ai poco-agent up to 0.5.4. Affected is the function WorkspaceManager._setup_session_persistence of the file executor/app/core/workspace.py of the component Claude File Handler. The manipulation results in incomplete cleanup. The attack may be performed from remote. Attacks of this nature are highly complex. The exploitability is told to be difficult. The exploit has been released to the public and may be used for attacks.4d CVE-2026-635452.4 BAJ

4.9%

——1Sharp and Toshiba Tec MFPs (multifunction printers) caches data internally when printing, and leave them uncleared. They may be accessed later by other users.13d