CyberSecBulletin
CVE-2026-45902NVD status: Undergoing Analysis

Linux: Use After Free

Published Updated By the CyberSecBulletin desk

CVE-2026-45902 is a high-severity use after free vulnerability in Linux, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions 81d3688c9a2158329391e08f2d0b8ba204216044, 74b5a88318db97d51bb40f774736553c2acd1514, cb5c743936edcebc51880eeb6bf04979b5c9438b as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.16% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Linux to 81d3688c9a2158329391e08f2d0b8ba204216044 or 74b5a88318db97d51bb40f774736553c2acd1514 or cb5c743936edcebc51880eeb6bf04979b5c9438b or 83c27fdd696ac13d023ef7a0345301be93209c53, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.15.202 or 6.1.165 or 6.6.128 or 6.12.75, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux32e4978bb920d047fe5de3ea42d176f267c01f63 up to, but not including, 81d3688c9a2158329391e08f2d0b8ba204216044; 32e4978bb920d047fe5de3ea42d176f267c01f63 up to, but not including, 74b5a88318db97d51bb40f774736553c2acd1514; 32e4978bb920d047fe5de3ea42d176f267c01f63 up to, but not including, cb5c743936edcebc51880eeb6bf04979b5c9438b; 32e4978bb920d047fe5de3ea42d176f267c01f63 up to, but not including, 83c27fdd696ac13d023ef7a0345301be93209c53; 32e4978bb920d047fe5de3ea42d176f267c01f63 up to, but not including, 4b6fb0b6124f558131e502e3ffd03e6583b3ace6; 32e4978bb920d047fe5de3ea42d176f267c01f63 up to, but not including, 8796910131a32ff29275052df768ef022929a394; 32e4978bb920d047fe5de3ea42d176f267c01f63 up to, but not including, 8005843369723d9c8975b7c4202d1b85d6125302; 5.1281d3688c9a2158329391e08f2d0b8ba204216044, 74b5a88318db97d51bb40f774736553c2acd1514, cb5c743936edcebc51880eeb6bf04979b5c9438b, 83c27fdd696ac13d023ef7a0345301be93209c53, 4b6fb0b6124f558131e502e3ffd03e6583b3ace6, 8796910131a32ff29275052df768ef022929a394
LinuxLinux Kernel5.12 up to, but not including, 5.15.202; 5.16 up to, but not including, 6.1.165; 6.2 up to, but not including, 6.6.128; 6.7 up to, but not including, 6.12.75; 6.13 up to, but not including, 6.18.14; 6.19 up to, but not including, 6.19.45.15.202, 6.1.165, 6.6.128, 6.12.75, 6.18.14, 6.19.4

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Official description

In the Linux kernel, the following vulnerability has been resolved: power: supply: bq256xx: Fix use-after-free in power_supply_changed() Using the `devm_` variant for requesting IRQ _before_ the `devm_` variant for allocating/registering the `power_supply` handle, means that the `power_supply` handle will be deallocated/unregistered _before_ the interrupt handler (since `devm_` naturally deallocates in reverse allocation order). This means that during removal, there is a race condition where an interrupt can fire just _after_ the `power_supply` handle has been freed, *but* just _before_ the corresponding unregistration of the IRQ handler has run. This will lead to the IRQ handler calling `power_supply_changed()` with a freed `power_supply` handle. Which usually crashes the system or otherwise silently corrupts the memory... Note that there is a similar situation which can also happen during `probe()`; the possibility of an interrupt firing _before_ registering the `power_supply` handle. This would then lead to the nasty situation of using the `power_supply` handle *uninitialized* in `power_supply_changed()`. Fix this racy use-after-free by making sure the IRQ is requested _after_ the registration of the `power_supply` handle.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Use After Free

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.

How developers prevent this class of flaw

  • Choose a language that provides automatic memory management.
  • When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.

More Use After Free vulnerabilities (CWE-416)

Timeline

  1. CVE record published.
  2. Record last changed materially (score, affected products, status or references).

References

Recent Use After Free vulnerabilities

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