CVE-2024-35840: Linux kernel · mptcp: use OPTION_MPTCP_MPJ_SYNACK in subflow_finish_connect()
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.5 Medium · fixed in 5.15.0-1057.63~20.04.1 : update Linux kernel when convenient.
Data as of 12 Nov 2026, 19:04 UTC
- Patch
- Available – fixed in 5.15.0-1057.63~20.04.1, 5.15.0-1060.69~20.04.1, 5.15.0-1055.63~20.04.1 +38
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 17 May 2024
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 12 Nov 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Patches and advisories
- ubuntu.com/security/notices/USN-6818-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-6819-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-6818-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-6819-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-6819-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-6818-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-6818-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-6819-4 (opens in a new tab)
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu Pro Realtime 24.04 LTSlinux-raspi-realtimepkg:deb/ubuntu/linux-raspi-realtime?arch=source&distro=realtime/nobleOther threats | Affected
| Fixed in
|
Ubuntu 22.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=jammyOther threats | Affected
| Fixed in
|
Ubuntu 22.04 LTSlinux-allwinner-5.19pkg:deb/ubuntu/linux-allwinner-5.19?arch=source&distro=jammyOther threats | Affected
| Fixed in– |
Ubuntu 22.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=jammyOther threats | Affected
| Fixed in
|
Ubuntu 22.04 LTSlinux-aws-5.19pkg:deb/ubuntu/linux-aws-5.19?arch=source&distro=jammyOther threats | Affected
| Fixed in– |
Ubuntu 22.04 LTSlinux-aws-6.2pkg:deb/ubuntu/linux-aws-6.2?arch=source&distro=jammyOther 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: mptcp: use OPTION_MPTCP_MPJ_SYNACK in subflow_finish_connect() subflow_finish_connect() uses four fields (backup, join_id, thmac, none) that may contain garbage unless OPTION_MPTCP_MPJ_SYNACK has been set in mptcp_parse_option()
References
- ubuntu.com/security/CVE-2024-35840 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2024-35840 (opens in a new tab)
- git.kernel.org/linus/be1d9d9d38da922bd4beeec5b6dd821ff5a1dfeb (opens in a new tab)
- git.kernel.org/stable/c/413b913507326972135d2977975dbff8b7f2c453 (opens in a new tab)
- git.kernel.org/stable/c/51e4cb032d49ce094605f27e45eabebc0408893c (opens in a new tab)
- git.kernel.org/stable/c/ad3e8f5c3d5c53841046ef7a947c04ad45a20721 (opens in a new tab)
- git.kernel.org/stable/c/76e8de7273a22a00d27e9b8b7d4d043d6433416a (opens in a new tab)
- git.kernel.org/stable/c/be1d9d9d38da922bd4beeec5b6dd821ff5a1dfeb (opens in a new tab)
- ubuntu.com/security/notices/USN-6818-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-6819-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-6818-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-6819-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-6819-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-6818-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-6818-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-6819-4 (opens in a new tab)