CVE-2026-72020: Linux kernel · ipvs: reset full ip_vs_seq structs in ip_vs_conn_new
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 9.8 Critical · fixed in 5.15.0-1117.124~20.04.1 : patch Linux kernel as a priority.
Data as of 26 Oct 2026, 12:55 UTC
- EPSS
- 0.7% chance of exploitation in 30 days – higher than 53% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.15.0-1117.124~20.04.1, 5.15.0-1123.132~20.04.1, 5.15.0-1122.131~20.04.1 +43
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 15 Aug 2026
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.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther 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
A patch is available and should be applied to affected Linux kernel versions to fully reset the ip_vs_seq structures in ip_vs_conn_new. The vendor advisory from Ubuntu confirms that this and other Linux kernel vulnerabilities have been fixed. Users should update their Linux kernel packages to the fixed versions as provided by their distribution vendors.
Description
A vulnerability in the Linux kernel's IP Virtual Server (ipvs) subsystem was resolved by fully resetting ip_vs_seq structures in the ip_vs_conn_new function. Previously, some fields were left uninitialized, which could cause stale slab data to be used in TCP sequence and acknowledgment number adjustments. This flaw could corrupt forwarded TCP flows when processing malformed sync messages. The issue affects specific Linux kernel versions and has a high CVSS score of 9.8. A patch is available to address this vulnerability.
References
- nvd.nist.gov/vuln/detail/CVE-2026-72020 (opens in a new tab)
- git.kernel.org/stable/c/2975324d164c552b028632f107b567302863b7f6 (opens in a new tab)
- git.kernel.org/stable/c/32c299e28b8eea6cbbd23b97dc61401e9ef9c445 (opens in a new tab)
- git.kernel.org/stable/c/3bf9a260188b2a5449cbddc032a749ab433fe328 (opens in a new tab)
- git.kernel.org/stable/c/6335ab62d5fc9ed875279238233fba3462c168f5 (opens in a new tab)
- git.kernel.org/stable/c/6378c5cb360eb1750f88839d7c3613ea92ac1816 (opens in a new tab)
- git.kernel.org/stable/c/83fb4c2c5344f02eac929f66de3c9d1adfcde04c (opens in a new tab)
- git.kernel.org/stable/c/9e36602cbec552286f7e691cfd366525c565ee74 (opens in a new tab)
- git.kernel.org/stable/c/d0eed7177e822cab83141e5c44b2aa345c7fd379 (opens in a new tab)
- ubuntu.com/security/CVE-2026-72020 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-72020 (opens in a new tab)
- git.kernel.org/linus/2975324d164c552b028632f107b567302863b7f6 (opens in a new tab)
- ubuntu.com/security/notices/USN-8781-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8876-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8878-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8879-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8877-1 (opens in a new tab)