virtio/vsock: Fix uninit-value in virtio_transport_recv_pkt()
Noroxi assessment
Priority: Monitor (action score 28/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.24% (FIRST EPSS).
- Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
- Fixed version: Linux Linux 0b8906fb48b99e993d6e8a12539f618f4854dd26, 34c4effacfc329aeca5635a69fd9e0f6c90b4101, cd12535b97dd7d18cf655ec78ce1cf1f29a576be.
Low priority for now. Upgrade to Linux Linux 0b8906fb48b99e993d6e8a12539f618f4854dd26, 34c4effacfc329aeca5635a69fd9e0f6c90b4101, cd12535b97dd7d18cf655ec78ce1cf1f29a576be or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
In the Linux kernel, the following vulnerability has been resolved: virtio/vsock: Fix uninit-value in virtio_transport_recv_pkt() KMSAN reported the following uninit-value access issue: ===================================================== BUG: KMSAN: uninit-value in virtio_transport_recv_pkt+0x1dfb/0x26a0 net/vmw_vsock/virtio_transport_common.c:1421 virtio_transport_recv_pkt+0x1dfb/0x26a0 net/vmw_vsock/virtio_transport_common.c:1421 vsock_loopback_work+0x3bb/0x5a0 net/vmw_vsock/vsock_loopback.c:120 process_one_work kernel/workqueue.c:2630 [inline] process_scheduled_works+0xff6/0x1e60 kernel/workqueue.c:2703 worker_thread+0xeca/0x14d0 kernel/workqueue.c:2784 kthread+0x3cc/0x520 kernel/kthread.c:388 ret_from_fork+0x66/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Uninit was stored to memory at: virtio_transport_space_update net/vmw_vsock/virtio_transport_common.c:1274 [inline] virtio_transport_recv_pkt+0x1ee8/0x26a0 net/vmw_vsock/virtio_transport_common.c:1415 vsock_loopback_work+0x3bb/0x5a0 net/vmw_vsock/vsock_loopback.c:120 process_one_work kernel/workqueue.c:2630 [inline] process_scheduled_works+0xff6/0x1e60 kernel/workqueue.c:2703 worker_thread+0xeca/0x14d0 kernel/workqueue.c:2784 kthread+0x3cc/0x520 kernel/kthread.c:388 ret_from_fork+0x66/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Uninit was created at: slab_post_alloc_hook+0x105/0xad0 mm/slab.h:767 slab_alloc_node mm/slub.c:3478 [inline] kmem_cache_alloc_node+0x5a2/0xaf0 mm/slub.c:3523 kmalloc_reserve+0x13c/0x4a0 net/core/skbuff.c:559 __alloc_skb+0x2fd/0x770 net/core/skbuff.c:650 alloc_skb include/linux/skbuff.h:1286 [inline] virtio_vsock_alloc_skb include/linux/virtio_vsock.h:66 [inline] virtio_transport_alloc_skb+0x90/0x11e0 net/vmw_vsock/virtio_transport_common.c:58 virtio_transport_reset_no_sock net/vmw_vsock/virtio_transport_common.c:957 [inline] virtio_transport_recv_pkt+0x1279/0x26a0 net/vmw_vsock/virtio_transport_common.c:1387 vsock_loopback_work+0x3bb/0x5a0 net/vmw_vsock/vsock_loopback.c:120 process_one_work kernel/workqueue.c:2630 [inline] process_scheduled_works+0xff6/0x1e60 kernel/workqueue.c:2703 worker_thread+0xeca/0x14d0 kernel/workqueue.c:2784 kthread+0x3cc/0x520 kernel/kthread.c:388 ret_from_fork+0x66/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 CPU: 1 PID: 10664 Comm: kworker/1:5 Not tainted 6.6.0-rc3-00146-g9f3ebbef746f #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-1.fc38 04/01/2014 Workqueue: vsock-loopback vsock_loopback_work ===================================================== The following simple reproducer can cause the issue described above: int main(void) { int sock; struct sockaddr_vm addr = { .svm_family = AF_VSOCK, .svm_cid = VMADDR_CID_ANY, .svm_port = 1234, }; sock = socket(AF_VSOCK, SOCK_STREAM, 0); connect(sock, (struct sockaddr *)&addr, sizeof(addr)); return 0; } This issue occurs because the `buf_alloc` and `fwd_cnt` fields of the `struct virtio_vsock_hdr` are not initialized when a new skb is allocated in `virtio_transport_init_hdr()`. This patch resolves the issue by initializing these fields during allocation.
- Published
- May 21, 2024
- Updated
- Jun 17, 2026
- EPSS
- 0.2% · 14th percentile
- CWE
- CWE-908
Report tools
Action score
28
Monitor
Low priority for now.
- CVSS
- 28 / 40 · 7.1 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.2%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| linux | linux kernel | cpe:2.3:o:linux:linux_kernel |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- linux linux kernel6.3 and later · before 6.6.2
Versions reported by the vendor
Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.
Linux Linux
- 6.3affected
- baddcc2c71572968cdaeee1c4ab3dc0ad90fa765 and later · before cd12535b97dd7d18cf655ec78ce1cf1f29a576beaffected · git
- 71dc9ec9ac7d3eee785cdc986c3daeb821381e20 and later · before 0b8906fb48b99e993d6e8a12539f618f4854dd26affected · git
- 71dc9ec9ac7d3eee785cdc986c3daeb821381e20 and later · before 34c4effacfc329aeca5635a69fd9e0f6c90b4101affected · git
- before 6.3not affected · semver
- 6.6.2 and later · up to and including 6.6.*not affected · semver
- 6.7 and laternot affected · original_commit_for_fix
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | linux | before 6.1.64-1 | 6.1.64-1 |
| Debian:13 | linux | before 6.6.8-1 | 6.6.8-1 |
Same product
linux: all recordsOther highest-scoring records for the same primary product.
- CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV89Now
- CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV85Now
- CVE-2016-5195Race condition in mm/gup.c in the Linux kernel 2.x through 4.x before 4.8.3 allows local users to gain privileges by leveraging incorrect haKEV83Now
Published before and after this one in the same product
- ← EarlierCVE-2023-52840May 21, 2024 · Input: synaptics-rmi4 - fix use after free in rmi_unregister_function()31Monitor
- ← EarlierCVE-2023-52841May 21, 2024 · media: vidtv: mux: Add check and kfree for kstrdup22Monitor
- Later →CVE-2023-52843May 21, 2024 · llc: verify mac len before reading mac header22Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| Linux Linux | 0b8906fb48b99e993d6e8a12539f618f4854dd26 | Vendor (CNA) |
| Linux Linux | 34c4effacfc329aeca5635a69fd9e0f6c90b4101 | Vendor (CNA) |
| Linux Linux | cd12535b97dd7d18cf655ec78ce1cf1f29a576be | Vendor (CNA) |
| debian:linux | 6.1.64-1 · Debian:12 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2024-50302182 days apartHID: core: zero-initialize the report bufferKEV52Plan
- CVE-2024-47685153 days apartnetfilter: nf_reject_ipv6: fix nf_reject_ip6_tcphdr_put()36Monitor
- CVE-2021-475533 days apartsched/scs: Reset task stack state in bringup_cpu()31Monitor
- CVE-2024-368989 days apartgpiolib: cdev: fix uninitialised kfifo31Monitor
- CVE-2024-2702220 days apartfork: defer linking file vma until vma is fully initialized31Monitor
- CVE-2024-50143170 days apartudf: fix uninit-value use in udf_get_fileshortad31Monitor
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Someone with local access to the system can trigger it.
- A low-privileged account is enough.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- none
- Availability
- high · the service can be disrupted
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- None
- Availability impact
- High
Weakness class (CWE)
CWE-908 · Use of Uninitialized ResourceCVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (2 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.