CVE-2024-49936: Linux kernel · net/xen-netback: prevent UAF in xenvif_flush_hash()
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 8.8 High · fixed in 5.4.0-1142.152~18.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 23:28 UTC
- Patch
- Available – fixed in 5.4.0-1142.152~18.04.1, 5.4.0-1147.154~18.04.1, 5.4.0-1145.154~18.04.1 +80
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 21 Oct 2024
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 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Patches and advisories
- ubuntu.com/security/notices/USN-7166-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7166-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7166-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7186-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7186-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7194-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7166-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-7276-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7277-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7301-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7303-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7304-1 (opens in a new tab)
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 24.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azure-6.11pkg:deb/ubuntu/linux-azure-6.11?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azure-nvidiapkg:deb/ubuntu/linux-azure-nvidia?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
In the Linux kernel, the following vulnerability has been resolved: net/xen-netback: prevent UAF in xenvif_flush_hash() During the list_for_each_entry_rcu iteration call of xenvif_flush_hash, kfree_rcu does not exist inside the rcu read critical section, so if kfree_rcu is called when the rcu grace period ends during the iteration, UAF occurs when accessing head->next after the entry becomes free. Therefore, to solve this, you need to change it to list_for_each_entry_safe.
References
- ubuntu.com/security/CVE-2024-49936 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2024-49936 (opens in a new tab)
- git.kernel.org/linus/0fa5e94a1811d68fbffa0725efe6d4ca62c03d12 (opens in a new tab)
- git.kernel.org/stable/c/a7f0073fcd12ed7de185ef2c0af9d0fa1ddef22c (opens in a new tab)
- git.kernel.org/stable/c/a0465723b8581cad27164c9073fd780904cd22d4 (opens in a new tab)
- git.kernel.org/stable/c/efcff6ce7467f01f0753609f420333f3f2ceceda (opens in a new tab)
- git.kernel.org/stable/c/143edf098b80669d05245b2f2367dd156a83a2c5 (opens in a new tab)
- git.kernel.org/stable/c/d408889d4b54f5501e4becc4dbbb9065143fbf4e (opens in a new tab)
- git.kernel.org/stable/c/54d8639af5568fc41c0e274fc3ec9cf86c59fcbb (opens in a new tab)
- git.kernel.org/stable/c/0fa5e94a1811d68fbffa0725efe6d4ca62c03d12 (opens in a new tab)
- ubuntu.com/security/notices/USN-7166-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7166-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7166-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7186-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7186-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7194-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7166-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-7276-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7277-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7301-1 (opens in a new tab)