Linux Kernel: Memory Leak (CVE-2026-98947)

What is affected, what to do

In the Linux kernel, the following vulnerability has been resolved: vsock: Fix memory leak in vmci_transport_recv_dgram_cb() During the closure of a datagram socket, the vmci_transport_recv_dgram_cb() function may be called, which will add the packets to the socket's backlog; then, after the receive queue is cleared, the __release_sock() function will move the packet back from the socket's backlog to the receive queue, which will lead to a memory leak. sock_close __sock_release __vsock_release // take ownership by user-space lock_sock_nested sock_set_flag(sk, SOCK_DEAD) vmci_transport_release vmci_dispatch_dgs vmci_datagram_invoke_guest_handler vmci_transport_recv_dgram_cb sk_receive_skb if (!sock_owned_by_user(sk)) [...] (!) else if sk_add_backlog() [...] (!) skb_queue_purge(&sk->sk_receive_queue) release_sock __release_sock // move all packets from the backlog // to the receive queue (!) sk_backlog_rcv vsock_queue_rcv_skb [...] __sock_queue_rcv_skb if (!sock_flag(sk, SOCK_DEAD)) // Since the socket is "dead", the function will not // be called sk->sk_data_ready(sk) sock_release_ownership(sk); sock_put Add a receive queue cleanup in the socket destructor to fix this. syzkaller report: unreferenced object 0xffff8880117bfb80 (size 240): comm "irq/56-vmw_vmci", pid 205, jiffies 4295064448 (age 73.992s) hex dump (first 32 bytes): 78 dc 26 1e 80 88 ff ff 78 dc 26 1e 80 88 ff ff x.&.....x.&..... 00 00 00 00 00 00 00 00 c0 da 26 1e 80 88 ff ff ..........&..... backtrace: [<ffffffff82be8d97>] __alloc_skb+0x287/0x330 net/core/skbuff.c:505 [<ffffffffa114bcbd>] vmci_transport_recv_dgram_cb+0xbd/0x210 [vmw_vsock_vmci_transport] [<ffffffffa05072c6>] vmci_datagram_invoke_guest_handler+0x366/0x450 [vmw_vmci] [<ffffffffa050ad75>] vmci_dispatch_dgs+0x235/0x490 [vmw_vmci] [<ffffffffa050b025>] vmci_interrupt+0x55/0x290 [vmw_vmci] [<ffffffff8137ad2b>] irq_thread_fn+0x8b/0x1a0 kernel/irq/manage.c:1205 [<ffffffff8137c7ae>] irq_thread+0x28e/0x530 kernel/irq/manage.c:1314 [<ffffffff81253dd6>] kthread+0x2e6/0x3a0 kernel/kthread.c:376 [<ffffffff81004392>] ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:295 Found by InfoTeCS on behalf of Linux Verification Center (linuxtesting.org) with Syzkaller.

Update Linux Kernel to version 6.12.113, Linux Kernel to version 6.18.57, Linux Kernel to version 7.2.11.

Affected: Linux Kernel lt 3.9..6.12.113
Linux Kernel lt 6.13..6.18.57
Linux Kernel lt 6.19..7.2.11
Fixed in: Linux Kernel 6.12.113
Linux Kernel 6.18.57
Linux Kernel 7.2.11
Linux Kernel 7.3

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Metrics

2.6

Priority

XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.

Source: Vendor (CNA), CVSS v3

2.6

CVSS v3

Severity Low on the scale from 0 to 10.

Source: BSI, Msrc Update Guide, CVE.org

0.2 %

EPSS score

Low — model estimates < 1% exploitation likelihood.

Source: FIRST EPSS, percentile 6.2

Show all metrics

Severity: Low
Priority (0–325) The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first? Read in glossary: 43.31 Methodology
Exploit maturity An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack. Read in glossary: no public PoC known
XIEM Effective CVSS XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command. Read in glossary: 2.6 Methodology
CVSS v3 CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions. Read in glossary: 2.6
EPSS score The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“. Read in glossary: 0.2 %; Low — model estimates < 1% exploitation likelihood.
EPSS percentile The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking. Read in glossary: 6.2; Low — this CVE sits in the lower 10% of all CVEs scored today.
KEV status The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching. Read in glossary: —
Published: 23.10.2026

Detection rules

No NEOSEC detection rule is available for this vulnerability yet.

Classification under NIS2 and CRA

Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

NIS2 NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management. Read in glossary: Handle the vulnerability in regular vulnerability handling under Art. 21(2)(e) NIS2.
CRA The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates. Read in glossary: From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
ISO/IEC 27001 ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security. Read in glossary: Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

Description

In the Linux kernel, the following vulnerability has been resolved: vsock: Fix memory leak in vmci_transport_recv_dgram_cb() During the closure of a datagram socket, the vmci_transport_recv_dgram_cb() function may be called, which will add the packets to the socket's backlog; then, after the receive queue is cleared, the __release_sock() function will move the packet back from the socket's backlog to the receive queue, which will lead to a memory leak. sock_close __sock_release __vsock_release // take ownership by user-space lock_sock_nested sock_set_flag(sk, SOCK_DEAD) vmci_transport_release vmci_dispatch_dgs vmci_datagram_invoke_guest_handler vmci_transport_recv_dgram_cb sk_receive_skb if (!sock_owned_by_user(sk)) [...] (!) else if sk_add_backlog() [...] (!) skb_queue_purge(&sk->sk_receive_queue) release_sock __release_sock // move all packets from the backlog // to the receive queue (!) sk_backlog_rcv vsock_queue_rcv_skb [...] __sock_queue_rcv_skb if (!sock_flag(sk, SOCK_DEAD)) // Since the socket is "dead", the function will not // be called sk->sk_data_ready(sk) sock_release_ownership(sk); sock_put Add a receive queue cleanup in the socket destructor to fix this. syzkaller report: unreferenced object 0xffff8880117bfb80 (size 240): comm "irq/56-vmw_vmci", pid 205, jiffies 4295064448 (age 73.992s) hex dump (first 32 bytes): 78 dc 26 1e 80 88 ff ff 78 dc 26 1e 80 88 ff ff x.&.....x.&..... 00 00 00 00 00 00 00 00 c0 da 26 1e 80 88 ff ff ..........&..... backtrace: [<ffffffff82be8d97>] __alloc_skb+0x287/0x330 net/core/skbuff.c:505 [<ffffffffa114bcbd>] vmci_transport_recv_dgram_cb+0xbd/0x210 [vmw_vsock_vmci_transport] [<ffffffffa05072c6>] vmci_datagram_invoke_guest_handler+0x366/0x450 [vmw_vmci] [<ffffffffa050ad75>] vmci_dispatch_dgs+0x235/0x490 [vmw_vmci] [<ffffffffa050b025>] vmci_interrupt+0x55/0x290 [vmw_vmci] [<ffffffff8137ad2b>] irq_thread_fn+0x8b/0x1a0 kernel/irq/manage.c:1205 [<ffffffff8137c7ae>] irq_thread+0x28e/0x530 kernel/irq/manage.c:1314 [<ffffffff81253dd6>] kthread+0x2e6/0x3a0 kernel/kthread.c:376 [<ffffffff81004392>] ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:295 Found by InfoTeCS on behalf of Linux Verification Center (linuxtesting.org) with Syzkaller.

Source: BSI CSAF, BSI WID Portal, Microsoft Security Update Guide, cvelistv5, NVD (NIST)

Affected products
		Affected versions	Fixed in
Linux	Linux	`6.19 – < 7.2.11` `3.9 – < 6.12.113` `—` `6.13 – < 6.18.57`	`7.2.11` `6.12.113` `7.3` `6.18.57`

Vendors and products

Linux Linux

References & sources

git.kernel.orgstable/c/0f8e2b2045355a0ee2008125e573435504b13cee
git.kernel.orgstable/c/4835dbcde5cc3ae37e0d0796052056b35fcae8bf
git.kernel.orgstable/c/7c24a4e87e219072e5e106f6791146cbf3b056b3
git.kernel.orgstable/c/9907db2b8e7ba70b442bb9dec86526a6511fac62

Changes to this CVE

Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).

23.10.2026ReceivedLinux

Description added or changed

New references:

Show 6 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Description	added	—	In the Linux kernel, the following vulnerability has been resolved: vsock: Fix memory leak in vmci_transport_recv_dgram_cb() During the closure of a datagram socket, the vmci_transport_recv_dgram_cb() function may be called, which will add the packets to the socket's backlog; then, after the receive queue is cleared, the __release_sock() function will move the packet back from the socket's backlog to the receive queue, which will lead to a memory leak. sock_close __sock_release __vsock_release // take ownership by user-space lock_sock_nested sock_set_flag(sk, SOCK_DEAD) vmci_transport_release vmci_dispatch_dgs vmci_datagram_invoke_guest_handler vmci_transport_recv_dgram_cb sk_receive_skb if (!sock_owned_by_user(sk)) [...] (!) else if sk_add_backlog() [...] (!) skb_queue_purge(&sk->sk_receive_queue) release_sock __release_sock // move all packets from the backlog // to the receive queue (!) sk_backlog_rcv vsock_queue_rcv_skb [...] __sock_queue_rcv_skb if (!sock_flag(sk, SOCK_DEAD)) // Since the socket is "dead", the function will not // be called sk->sk_data_ready(sk) sock_release_ownership(sk); sock_put Add a receive queue cleanup in the socket destructor to fix this. syzkaller report: unreferenced object 0xffff8880117bfb80 (size 240): comm "irq/56-vmw_vmci", pid 205, jiffies 4295064448 (age 73.992s) hex dump (first 32 bytes): 78 dc 26 1e 80 88 ff ff 78 dc 26 1e 80 88 ff ff x.&.....x.&..... 00 00 00 00 00 00 00 00 c0 da 26 1e 80 88 ff ff ..........&..... backtrace: [<ffffffff82be8d97>] __alloc_skb+0x287/0x330 net/core/skbuff.c:505 [<ffffffffa114bcbd>] vmci_transport_recv_dgram_cb+0xbd/0x210 [vmw_vsock_vmci_transport] [<ffffffffa05072c6>] vmci_datagram_invoke_guest_handler+0x366/0x450 [vmw_vmci] [<ffffffffa050ad75>] vmci_dispatch_dgs+0x235/0x490 [vmw_vmci] [<ffffffffa050b025>] vmci_interrupt+0x55/0x290 [vmw_vmci] [<ffffffff8137ad2b>] irq_thread_fn+0x8b/0x1a0 kernel/irq/manage.c:1205 [<ffffffff8137c7ae>] irq_thread+0x28e/0x530 kernel/irq/manage.c:1314 [<ffffffff81253dd6>] kthread+0x2e6/0x3a0 kernel/kthread.c:376 [<ffffffff81004392>] ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:295 Found by InfoTeCS on behalf of Linux Verification Center (linuxtesting.org) with Syzkaller.
Affected versions (publisher)	added	—	New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/98xxx/CVE-2026-98947.json">CVE-2026-98947</a>
Reference	added	—	https://git.kernel.org/stable/c/0f8e2b2045355a0ee2008125e573435504b13cee
Reference	added	—	https://git.kernel.org/stable/c/4835dbcde5cc3ae37e0d0796052056b35fcae8bf
Reference	added	—	https://git.kernel.org/stable/c/7c24a4e87e219072e5e106f6791146cbf3b056b3
Reference	added	—	https://git.kernel.org/stable/c/9907db2b8e7ba70b442bb9dec86526a6511fac62

Source identifier: 416baaa9-dc9f-4396-8d5f-8c081fb06d67