Vulnerabilities

Vulnerability · CVE-2026-31654

In the Linux kernel, the following vulnerability has been resolved: mm/vma: fix memory leak in __mmap_region() commit 605f6586ecf7 ("mm/vma: do not leak memory when .m…

Published Apr 24, 2026 · catalog updated Jun 17, 2026 · linux kernel

Check if you run it

No confirmed exploitation is on record for CVE-2026-31654. EPSS is 0.16%. Act only if a listed version of linux kernel is installed.

Gaps on this record

  • No vendor fix or required action is stored. Compare the linked advisory before you change production.
Severity
Medium5.5
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.16%
Remediation
Advisory link
Affected products
cpe linux/linux kernel

In the Linux kernel, the following vulnerability has been resolved: mm/vma: fix memory leak in __mmap_region() commit 605f6586ecf7 ("mm/vma: do not leak memory when .mmap_prepare swaps the file") handled the success path by skipping get_file() via file_doesnt_need_get, but missed the error path. When /dev/zero is mmap'd with MAP_SHARED, mmap_zero_prepare() calls shmem_zero_setup_desc() which allocates a new shmem file to back the mapping. If __mmap_new_vma() subsequently fails, this replacement file is never fput()'d - the original is released by ksys_mmap_pgoff(), but nobody releases the new one. Add fput() for the swapped file in the error path. Reproducible with fault injection. FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 1 CPU: 2 UID: 0 PID: 366 Comm: syz.7.14 Not tainted 7.0.0-rc6 #2 PREEMPT(full) Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: dump_stack_lvl+0x164/0x1f0 should_fail_ex+0x525/0x650 should_failslab+0xdf/0x140 kmem_cache_alloc_noprof+0x78/0x630 vm_area_alloc+0x24/0x160 __mmap_region+0xf6b/0x2660 mmap_region+0x2eb/0x3a0 do_mmap+0xc79/0x1240 vm_mmap_pgoff+0x252/0x4c0 ksys_mmap_pgoff+0xf8/0x120 __x64_sys_mmap+0x12a/0x190 do_syscall_64+0xa9/0x580 entry_SYSCALL_64_after_hwframe+0x76/0x7e kmemleak: 1 new suspected memory leaks (see /sys/kernel/debug/kmemleak) BUG: memory leak unreferenced object 0xffff8881118aca80 (size 360): comm "syz.7.14", pid 366, jiffies 4294913255 hex dump (first 32 bytes): 00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00 .....N.......... ff ff ff ff ff ff ff ff c0 28 4d ae ff ff ff ff .........(M..... backtrace (crc db0f53bc): kmem_cache_alloc_noprof+0x3ab/0x630 alloc_empty_file+0x5a/0x1e0 alloc_file_pseudo+0x135/0x220 __shmem_file_setup+0x274/0x420 shmem_zero_setup_desc+0x9c/0x170 mmap_zero_prepare+0x123/0x140 __mmap_region+0xdda/0x2660 mmap_region+0x2eb/0x3a0 do_mmap+0xc79/0x1240 vm_mmap_pgoff+0x252/0x

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  • cpe linux/linux kernel6.19
  • cpe linux/linux kernel7.0

How to fix CVE-2026-31654

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2026-31654. EPSS is 0.16%. Act only if a listed version of linux kernel is installed.

Which versions are affected?

Compare what you have installed with linux/linux kernel 6.19; linux/linux kernel 7.0. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

CWE-401: Missing Release of Memory after Effective Lifetime. EPSS 0.16%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Apr 24, 2026 · NIST NVD

    Detected

    In the Linux kernel, the following vulnerability has been resolved: mm/vma: fix memory leak in __mmap_region() commit 605f6586ecf7 ("mm/vma: do not leak memory when .mmap_prepare swaps the file") handled the success path by skipping get_file() via file_doesnt_need_get, but missed the error path. When /dev/zero is mmap'd with MAP_SHARED, mmap_zero_prepare() calls shmem_zero_setup_desc() which alloc

  2. Jun 17, 2026 · NIST NVD

    Updated

    In the Linux kernel, the following vulnerability has been resolved: mm/vma: fix memory leak in __mmap_region() commit 605f6586ecf7 ("mm/vma: do not leak memory when .mmap_prepare swaps the file") handled the success path by skipping get_file() via file_doesnt_need_get, but missed the error path. When /dev/zero is mmap'd with MAP_SHARED, mmap_zero_prepare() calls shmem_zero_setup_desc() which alloc

Sources

  • CVE.orgVulnerability recordCVE-2026-31654

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2026-31654

    30-day exploitation probability 0.2%

    first.org
  • NIST NVDVulnerability recordCVE-2026-31654

    In the Linux kernel, the following vulnerability has been resolved: mm/vma: fix memory leak in __mmap_region() commit 605f6586ecf7 ("mm/vma: do not leak memory when .mmap_prepare swaps the file") handled the success path by skipping get_file() via file_doesnt_need_get, but miss

    nvd.nist.gov

References

Freshness

Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.