CVE-2026-43128: Linux kernel · RDMA/umem: Fix double dma_buf_unpin in failure path
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 7.8 High · fixed in d3e32e2f3262f1b25d77c085ace38e2cc4ad75cf : patch Linux kernel soon.
Data as of 26 Oct 2026, 17:30 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 3% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Total control over the software or total information disclosure
CISA SSVC assessment, 2026-10-16.
- Patch
- Available – fixed in d3e32e2f3262f1b25d77c085ace38e2cc4ad75cf, ba3bf0f1bf1d5d0404678485e872980532fcc2c4, b324327ff6f48d8065dca67eb3b91357e72726bd +3
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 6 May 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 |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
AI-suggested
A fix is available in the Linux kernel as indicated by the fixed commit versions. Users should upgrade to a patched kernel version that includes the commits identified (e.g., those referenced by the fixed commit hashes). No additional mitigation is required beyond applying the official fix.
Description
CVE-2026-43128 is a high-severity vulnerability in the Linux kernel's RDMA/umem subsystem affecting version 5.16. It involves a double unpinning of dma_buf in a failure path, which can lead to memory management issues. The flaw occurs when a failure in ib_umem_dmabuf_map_pages() causes an immediate unpin without clearing the pinned flag, resulting in a second unpin during cleanup. This has been fixed by removing the immediate unpin and relying on the proper release path to handle unpinning.
References
- git.kernel.org/stable/c/70542b69abff34d24b11ae0bb200cc7a766d18df (opens in a new tab)
- git.kernel.org/stable/c/b324327ff6f48d8065dca67eb3b91357e72726bd (opens in a new tab)
- git.kernel.org/stable/c/ba3bf0f1bf1d5d0404678485e872980532fcc2c4 (opens in a new tab)
- git.kernel.org/stable/c/d3e32e2f3262f1b25d77c085ace38e2cc4ad75cf (opens in a new tab)
- git.kernel.org/stable/c/40126bcbefa79ea86672e05dae608596bab38319 (opens in a new tab)
- git.kernel.org/stable/c/104016eb671e19709721c1b0048dd912dc2e96be (opens in a new tab)