CVE-2025-39718: Linux hwe edge · In the Linux kernel, the following vulnerability has been resolved: vsock/virtio: Validate length in packet header before skb_put() When receiving a
Affects linux-hwe-edgeSource GCVE Database
Not known to be exploited · CVSS 8.4 Medium : upgrade to 8.10 when convenient.
Data as of 26 Oct 2026, 06:26 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 5% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 8.10
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 5 Sep 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.
What to do
Upgrade redhat/kernel to 8.10.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Red Hatredhat/kernelpkg:rpm/redhat/kernelOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Red Hat has released an official security update for Red Hat Enterprise Linux 8 and related products that fixes this vulnerability. Users should apply the update as described in Red Hat advisory RHSA-2025:21398 and reboot affected systems to ensure the fix is applied. No additional mitigation steps are required beyond applying the official patch and rebooting.
Description
In the Linux kernel, the following vulnerability has been resolved: vsock/virtio: Validate length in packet header before skb_put() When receiving a vsock packet in the guest, only the virtqueue buffer size is validated prior to virtio_vsock_skb_rx_put(). Unfortunately, virtio_vsock_skb_rx_put() uses the length from the packet header as the length argument to skb_put(), potentially resulting in SKB overflow if the host has gone wonky. Validate the length as advertised by the packet header before calling virtio_vsock_skb_rx_put().
References
- access.redhat.com/errata/RHSA-2025:21397 (opens in a new tab)
- access.redhat.com/security/updates/classification/ (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2393507 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/advisories/2025/rhsa-2025_21397.json (opens in a new tab)
- ubuntu.com/security/CVE-2025-39718 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-39718 (opens in a new tab)
- git.kernel.org/linus/0dab92484474587b82e8e0455839eaf5ac7bf894 (opens in a new tab)
- git.kernel.org/stable/c/0dab92484474587b82e8e0455839eaf5ac7bf894 (opens in a new tab)
- git.kernel.org/stable/c/676f03760ca1d69c2470cef36c44dc152494b47c (opens in a new tab)
- git.kernel.org/stable/c/969b06bd8b7560efb100a34227619e7d318fbe05 (opens in a new tab)
- git.kernel.org/stable/c/ee438c492b2e0705d819ac0e25d04fae758d8f8f (opens in a new tab)
- git.kernel.org/stable/c/faf332a10372390ce65d0b803888f4b25a388335 (opens in a new tab)
- ubuntu.com/security/notices/USN-8028-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8028-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8031-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8028-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8028-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8028-5 (opens in a new tab)
- ubuntu.com/security/notices/USN-8031-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8028-6 (opens in a new tab)
- ubuntu.com/security/notices/USN-8031-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8052-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8028-7 (opens in a new tab)
- ubuntu.com/security/notices/USN-8028-8 (opens in a new tab)