CVE-2026-31702
published 2026-05-01CVE-2026-31702: In the Linux kernel, the following vulnerability has been resolved: f2fs: fix use-after-free of sbi in f2fs_compress_write_end_io() In…
PriorityP340high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.12%
2.1th percentile
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix use-after-free of sbi in f2fs_compress_write_end_io()
In f2fs_compress_write_end_io(), dec_page_count(sbi, type) can bring
the F2FS_WB_CP_DATA counter to zero, unblocking
f2fs_wait_on_all_pages() in f2fs_put_super() on a concurrent unmount
CPU. The unmount path then proceeds to call
f2fs_destroy_page_array_cache(sbi), which destroys
sbi->page_array_slab via kmem_cache_destroy(), and eventually
kfree(sbi). Meanwhile, the bio completion callback is still executing:
when it reaches page_array_free(sbi, ...), it dereferences
sbi->page_array_slab — a destroyed slab cache — to call
kmem_cache_free(), causing a use-after-free.
This is the same class of bug as CVE-2026-23234 (which fixed the
equivalent race in f2fs_write_end_io() in data.c), but in the
compressed writeback completion path that was not covered by that fix.
Fix this by moving dec_page_count() to after page_array_free(), so
that all sbi accesses complete before the counter decrement that can
unblock unmount. For non-last folios (where atomic_dec_return on
cic->pending_pages is nonzero), dec_page_count is called immediately
before returning — page_array_free is not reached on this path, so
there is no post-decrement sbi access. For the last folio,
page_array_free runs while the F2FS_WB_CP_DATA counter is still
nonzero (this folio has not yet decremented it), keeping sbi alive,
and dec_page_count runs as the final operation.
Affected
13 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 5.6 < 6.6.136 | 6.6.136 |
| linux | linux_kernel | >= 6.13 < 6.18.25 | 6.18.25 |
| linux | linux_kernel | >= 6.19 < 7.0.2 | 7.0.2 |
| linux | linux_kernel | >= 6.7 < 6.12.84 | 6.12.84 |
| ubuntu | linux | — | — |
| ubuntu | linux-aws | — | — |
| ubuntu | linux-gcp | — | — |
| ubuntu | linux-ibm | — | — |
| ubuntu | linux-nvidia | — | — |
| ubuntu | linux-oracle | — | — |
| ubuntu | linux-raspi | — | — |
| ubuntu | linux-realtime | — | — |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
vendor_redhat7.8HIGH
vendor_ubuntu2.0LOW
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Ubuntu
Linux kernel (NVIDIA) vulnerabilities
vendor_ubuntu·2026-07-06·CVSS 2.0
CVE-2026-46009 [LOW] Linux kernel (NVIDIA) vulnerabilities
Title: Linux kernel (NVIDIA) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD processors did not properly clear data in
the floating point divider unit during speculative execution. A local
attacker could use this to expose sensitive information. (CVE-2025-54505)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- Rados block device (RBD) driver;
- Compressed RAM block device driver;
- Character device driver;
- TPM device driver;
- Hardware crypto device drivers;
- EDAC drivers;
- GPU drivers;
- Greybus drive
Ubuntu
Linux kernel (Raspberry Pi) vulnerabilities
vendor_ubuntu·2026-07-02·CVSS 2.0
CVE-2026-46316 [LOW] Linux kernel (Raspberry Pi) vulnerabilities
Title: Linux kernel (Raspberry Pi) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD processors did not properly clear data in
the floating point divider unit during speculative execution. A local
attacker could use this to expose sensitive information. (CVE-2025-54505)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- Rados block device (RBD) driver;
- Compressed RAM block device driver;
- Character device driver;
- TPM device driver;
- Hardware crypto device drivers;
- EDAC drivers;
- GPU drivers;
- Greybus
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-07-01·CVSS 2.0
CVE-2026-46042 [LOW] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD processors did not properly clear data in
the floating point divider unit during speculative execution. A local
attacker could use this to expose sensitive information. (CVE-2025-54505)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- Rados block device (RBD) driver;
- Compressed RAM block device driver;
- Character device driver;
- TPM device driver;
- Hardware crypto device drivers;
- EDAC drivers;
- GPU drivers;
- Greybus drivers;
- HID
Red Hat
kernel: f2fs: fix use-after-free of sbi in f2fs_compress_write_end_io()
vendor_redhat·2026-05-01·CVSS 7.8
CVE-2026-31702 [HIGH] CWE-825 kernel: f2fs: fix use-after-free of sbi in f2fs_compress_write_end_io()
kernel: f2fs: fix use-after-free of sbi in f2fs_compress_write_end_io()
A flaw was found in the Linux kernel's F2FS (Flash-Friendly File System) component. A use-after-free vulnerability exists in the `f2fs_compress_write_end_io()` function. This flaw is caused by a race condition during the compressed writeback completion path, where the system attempts to access memory that has already been deallocated. A local attacker could potentially exploit this to cause a system crash, leading to a denial of service.
Package: kernel (Red Hat Enterprise Linux 10) - Not affected
Package: kernel (Red Hat Enterprise Linux 6) - Not affected
Package: kernel (Red Hat Enterprise Linux 7) - Not affected
Package: kernel-rt (Red Hat Enterprise Linux 7) - Not affected
Package: kernel (Red Hat Enterprise
GHSA
GHSA-5c3m-p5m6-p659: In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix use-after-free of sbi in f2fs_compress_write_end_io()
In f2fs_compress
ghsa_unreviewed·2026-05-01·CVSS 7.8
CVE-2026-31702 [HIGH] CWE-416 GHSA-5c3m-p5m6-p659: In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix use-after-free of sbi in f2fs_compress_write_end_io()
In f2fs_compress
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix use-after-free of sbi in f2fs_compress_write_end_io()
In f2fs_compress_write_end_io(), dec_page_count(sbi, type) can bring
the F2FS_WB_CP_DATA counter to zero, unblocking
f2fs_wait_on_all_pages() in f2fs_put_super() on a concurrent unmount
CPU. The unmount path then proceeds to call
f2fs_destroy_page_array_cache(sbi), which destroys
sbi->page_array_slab via kmem_cache_destroy(), and eventually
kfree(sbi). Meanwhile, the bio completion callback is still executing:
when it reaches page_array_free(sbi, ...), it dereferences
sbi->page_array_slab — a destroyed slab cache — to call
kmem_cache_free(), causing a use-after-free.
This is the same class of bug as CVE-2026-23234 (which fixed the
equivalent race in f2fs_wr
No detection rules found.
No public exploits indexed.
Rapid7
Patch Tuesday - May 2026
blogs_rapid7·2026-05-13·CVSS 10.0
CVE-2026-41089 [CRITICAL] Patch Tuesday - May 2026
Microsoft is publishing 137 vulnerabilities on May 2026 Patch Tuesday . Microsoft is not aware of exploitation in the wild or public disclosure for any of these vulnerabilities. So far this month, Microsoft has provided patches to address 133 browser vulnerabilities, which are not included in the Patch Tuesday count above.
## Windows Netlogon: critical RCE
Anyone responsible for securing a domain controller should prioritize remediation of CVE-2026-41089 , which is a critical stack-based buffer overflow in Windows Netlogon with a CVSS v3 base score of 9.8. Exploitation leads to execution in the context of the Netlogon service, so that’s SYSTEM privileges on the domain controller. For most pentesters, that’s the point at which the customer report more or less writes itself. No privileges
Bugzilla
CVE-2026-31702 kernel: f2fs: fix use-after-free of sbi in f2fs_compress_write_end_io()
bugzilla·2026-05-01·CVSS 7.8
CVE-2026-31702 [HIGH] CVE-2026-31702 kernel: f2fs: fix use-after-free of sbi in f2fs_compress_write_end_io()
CVE-2026-31702 kernel: f2fs: fix use-after-free of sbi in f2fs_compress_write_end_io()
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix use-after-free of sbi in f2fs_compress_write_end_io()
In f2fs_compress_write_end_io(), dec_page_count(sbi, type) can bring
the F2FS_WB_CP_DATA counter to zero, unblocking
f2fs_wait_on_all_pages() in f2fs_put_super() on a concurrent unmount
CPU. The unmount path then proceeds to call
f2fs_destroy_page_array_cache(sbi), which destroys
sbi->page_array_slab via kmem_cache_destroy(), and eventually
kfree(sbi). Meanwhile, the bio completion callback is still executing:
when it reaches page_array_free(sbi, ...), it dereferences
sbi->page_array_slab — a destroyed slab cache — to call
kmem_cache_free(), causing a use-after-free.
Thi
https://git.kernel.org/stable/c/2c97dcb6147c8f7f25c629b93be1e69617de5d4ahttps://git.kernel.org/stable/c/39d4ee19c1e7d753dd655aebee632271b171f43ahttps://git.kernel.org/stable/c/57bc678f36ac03281e877c6b84877b43f964143fhttps://git.kernel.org/stable/c/c76cf339b87975ae5b2c06d2d774d5667d25a12ahttps://git.kernel.org/stable/c/ef57cd3329b40c739b9a2e1a8a21ecc4171c6280https://git.kernel.org/stable/c/f5154cf3ce1c8193f0c1891d3769f62740cfe6fe
2026-05-01
Published