CVE-2026-43090General(linux / linux_kernel)

LOWCVSS 5.5 · MEDIUM

Exploitation ongoing with high activity in latest observed window (1 mentions)

Immediate actions

  • Prioritize remediation for linux linux_kernel systems immediately
  • Assume compromise if assets are exposed
  • Track advisory updates for patch or workaround availability

Recommended action window: Immediate (within 24h)

NVD description

In the Linux kernel, the following vulnerability has been resolved: xfrm: fix refcount leak in xfrm_migrate_policy_find syzkaller reported a memory leak in xfrm_policy_alloc: BUG: memory leak unreferenced object 0xffff888114d79000 (size 1024): comm "syz.1.17", pid 931 ... xfrm_policy_alloc+0xb3/0x4b0 net/xfrm/xfrm_policy.c:432 The root cause is a double call to xfrm_pol_hold_rcu() in xfrm_migrate_policy_find(). The lookup function already returns a policy with held reference, making the second call redundant. Remove the redundant xfrm_pol_hold_rcu() call to fix the refcount imbalance and prevent the memory leak. Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

3.5/ 10 priority

Sources & remediation

Priority

LOW

Exploitation

ACTIVE

PoC

NONE

Patch

AVAILABLE

Momentum

STABLE

Are you affected?

If you run products in this scope, you should treat this CVE as relevant to your environment.

  • linux_kernel

Threat summary

  • Active exploitation appears in 1 classified signals
  • 2 mentions across 2 observed days
  • Momentum state: stable

What's happening

  • Active exploitation reported across 1 signal
  • Technical details provided in 1 signal
  • General: 1 classified signal
  • Peaked 1d ago at 1 mentions (2026-05-06); latest day: 1
  • 2 total mentions across 2 days

Affected systems

Vendors
Products
linux_kernel

1 version affected across 1 product

Deep dive

Activity timeline2 mentions / 2d
00111Mentions · 2026-05-06: 1Mentions · 2026-05-07: 1Active Exploitation · 2026-05-07: 1Technical Details · 2026-05-06: 105-0605-07
Signal classification2 categories
General
150.0%
Active Exploitation
150.0%
Referenced assets2 URLs
Classification over time
DateTotalLabels
2026-05-061
General1
2026-05-071
Active Exploitation1
Full discourse2 posts
  • VulDB 🛡@vuldb
    Active Exploitation

    Some increased actor activities are shown targeting Linux Kernel (CVE-2026-43090) https://vuldb.com/vuln/361314/cti

    Post summary

    The message reports increased actor activity targeting Linux Kernel CVE-2026-43090, indicating active exploitation, but provides no PoC, patch, or vulnerability details.

    0101176
    2.1K followersView on X
  • Vulmon Vulnerability Feed@VulmonFeeds
    General

    CVE-2026-43090 Refcount Leak in Linux Kernel xfrm_migrate_policy_find Function https://vulmon.com/vulnerabilitydetails?qid=CVE-2026-43090

    Post summary

    The entry references CVE-2026-43090, noting a reference count leak in the Linux kernel’s xfrm_migrate_policy_find function, and links to a vulnerability details page without further technical or exploit details.

    0000048
    4.0K followersView on X
CPE platform detail8 entries

8 of 8 entries

PartVendorProductVersionTarget SWTarget HW
OSlinuxlinux_kernel---
OSlinuxlinux_kernel7.0--
OSlinuxlinux_kernel7.0--
OSlinuxlinux_kernel7.0--
OSlinuxlinux_kernel7.0--
OSlinuxlinux_kernel7.0--
OSlinuxlinux_kernel7.0--
OSlinuxlinux_kernel7.0--

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