smb: client: fix in-place encryption corruption in SMB2_write()
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · High · High
- Fix status
- Partial Red Hat: 3 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.
Summary
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix in-place encryption corruption in SMB2_write() SMB2_write() places write payload in iov[1..n] as part of rq_iov. smb3_init_transform_rq() pointer-shares rq_iov, so crypt_message() encrypts iov[1] in-place, replacing the original plaintext with ciphertext. On a replayable error, the retry sends the same iov[1] which now contains ciphertext instead of the original data, resulting in corruption. The corruption is most likely to be observed when connections are unstable, as reconnects trigger write retries that re-send the already-encrypted data. This affects SFU mknod, MF symlinks, etc. On kernels before 6.10 (prior to the netfs conversion), sync writes also used this path and were similarly affected. The async write path wasn't unaffected as it uses rq_iter which gets deep-copied. Fix by moving the write payload into rq_iter via iov_iter_kvec(), so smb3_init_transform_rq() deep-copies it before encryption.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 4.11 and later | 6.6.130, 6.12.78, 6.18.19, 6.19.9, 7.0 | Patch available | CNA |
- Linux VendorLinux Affected 4.11 and later Fixed in 6.6.130, 6.12.78, 6.18.19, 6.19.9, 7.0 Patch available CNA
CPE configurations NVD · 4
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 4.11 to before 6.6.130; 6.7 to before 6.12.78; 6.13 to before 6.18.19; 6.19 to before 6.19.9 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:* | 7.0 rc1 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:* | 7.0 rc2 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:* | 7.0 rc3 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 4.11 to before 6.6.130; 6.7 to before 6.12.78; 6.13 to before 6.18.19; 6.19 to before 6.19.9 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:* Versions 7.0 rc1 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:* Versions 7.0 rc2 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:* Versions 7.0 rc3 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 6.6.130, 6.12.78, 6.18.19, 6.19.9, 7.0
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
Not affected: 2 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
Timeline
- 2026-10-02 Threatist record created from CVE-2026-43362
- 2026-10-03 Alias added: GHSA-3mqh-w39c-q3pj
- 2026-10-16 CISA SSVC decision points changed
- 2026-10-19 Weakness changed · CISA ADP
References
Patch 5
- https://git.kernel.org/stable/c/438e77435aee2894d5edf90be5c87004a57f6258
- https://git.kernel.org/stable/c/52327268224fb9ccc7ecfbbdfdfff54b6e93c518
- https://git.kernel.org/stable/c/92e64f1852f455f57d0850989e57c30d7fac7d95
- https://git.kernel.org/stable/c/aea5e37388a080361110ab5790f57ae0af383650
- https://git.kernel.org/stable/c/d78840a6a38d312dc1a51a65317bb67e46f0b929
More Linux Kernel vulnerabilities
- TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
- TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
Sources
- CVE-2026-43362 · CVE Program
- CVE-2026-43362 · NVD
- FIRST EPSS
- GHSA-3mqh-w39c-q3pj · GitHub Advisory Database · CC BY 4.0
- CVE-2026-43362 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences