net/smc: fix use-after-free in smc_rx_pipe_buf_release()
Noroxi assessment
Priority: Monitor (action score 31/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.16% (FIRST EPSS).
- Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
- Fixed version: Linux Linux 0761e49aa78c2f1362511054c6e9670653858837, 0926f59ca0f94120895b92180c636a48d0ed3a6d, 6a644a7340df978785f3109d1e0726a982ce2c6f; azl3 kernel 6.6.152.1-1 on Azure Linux 3.0 6.6.157.1-1.
- Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).
Low priority for now. Upgrade to Linux Linux 0761e49aa78c2f1362511054c6e9670653858837, 0926f59ca0f94120895b92180c636a48d0ed3a6d, 6a644a7340df978785f3109d1e0726a982ce2c6f; azl3 kernel 6.6.152.1-1 on Azure Linux 3.0 6.6.157.1-1 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
In the Linux kernel, the following vulnerability has been resolved: net/smc: fix use-after-free in smc_rx_pipe_buf_release() smc_rx_splice() hands RMB pages to a pipe and takes a socket reference per entry so the smc_sock stays alive until the reader finishes. The connection does not: a concurrent close runs smc_conn_free(), which releases the receive buffer back to the link group pool. smc_rx_pipe_buf_release() tests sk_state before taking the socket lock. The state can change between the test and the lock, and smc_rx_update_cons() then dereferences conn->rmb_desc and walks conn->lgr, which smc_conn_free() has already released. On the is_reg_err path smcr_buf_unuse() frees the descriptor outright, so this is a use-after-free. Take the socket lock first and test conn->freed instead. smc_conn_free() sets that flag before releasing anything, and every caller holds the socket lock. The two paths exclude each other: either the pipe release runs first with everything valid, or it sees the flag and skips the update.
- Published
- Sep 11, 2026
- Updated
- Oct 19, 2026
- EPSS
- 0.1% · 5th percentile
- CWE
- —
Report tools
Action score
31
Monitor
Low priority for now.
- CVSS
- 31 / 40 · 7.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.1%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · Linux
- 7.8
- NVD has not scored this yet; the score shown is the CNA’s.
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
—
Versions reported by the vendor
Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.
Linux Linux
- 4.18affected
- 9014db202cb764b8e14c53e7bacc81f9a1a2ba7f and later · before dadd97c8296b23aa816e91ed70041820ae087baaaffected · git
- 9014db202cb764b8e14c53e7bacc81f9a1a2ba7f and later · before df441f3efbb50eb0f120b8de4bf441c31fb0551daffected · git
- 9014db202cb764b8e14c53e7bacc81f9a1a2ba7f and later · before 6a644a7340df978785f3109d1e0726a982ce2c6faffected · git
- 9014db202cb764b8e14c53e7bacc81f9a1a2ba7f and later · before 0761e49aa78c2f1362511054c6e9670653858837affected · git
- 9014db202cb764b8e14c53e7bacc81f9a1a2ba7f and later · before 0926f59ca0f94120895b92180c636a48d0ed3a6daffected · git
- 9014db202cb764b8e14c53e7bacc81f9a1a2ba7f and later · before c924884743e948e25625b7fbf3ee2a9325a204a7affected · git
- before 4.18not affected · semver
- 6.1.188 and later · up to and including 6.1.*not affected · semver
- 6.6.157 and later · up to and including 6.6.*not affected · semver
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | linux | before 6.1.190-1 | 6.1.190-1 |
| Debian:12 | linux-6.12 | before 6.12.111-1~deb12u1 | 6.12.111-1~deb12u1 |
| Debian:13 | linux | before 6.12.111-1 | 6.12.111-1 |
| Debian:14 | linux | before 7.2.6-1 | 7.2.6-1 |
Same product
linux: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-74705udp: fix potential use-after-free in tunnel segmentation40Plan
- CVE-2026-74612veth: fix skb length accounting after XDP frag adjustment40Plan
- CVE-2026-74475vxlan: use neigh_ha_snapshot() in route_shortcircuit()40Plan
Published before and after this one in the same product
- ← EarlierCVE-2026-80980Sep 11, 2026 · net/smc: stop killed, freed and out_of_sync sharing a byte39Monitor
- ← EarlierCVE-2026-80981Sep 11, 2026 · net/smc: fix use-after-free of the LLC qentry in smc_llc_srv_add_link()39Monitor
- Later →CVE-2026-80983Sep 11, 2026 · net/smc: fix socket refcount leak in smc_switch_conns()0Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| Linux Linux | 0761e49aa78c2f1362511054c6e9670653858837 | Vendor (CNA) |
| Linux Linux | 0926f59ca0f94120895b92180c636a48d0ed3a6d | Vendor (CNA) |
| Linux Linux | 6a644a7340df978785f3109d1e0726a982ce2c6f | Vendor (CNA) |
| Linux Linux | c924884743e948e25625b7fbf3ee2a9325a204a7 | Vendor (CNA) |
| Linux Linux | dadd97c8296b23aa816e91ed70041820ae087baa | Vendor (CNA) |
| Linux Linux | df441f3efbb50eb0f120b8de4bf441c31fb0551d | Vendor (CNA) |
| azl3 kernel 6.6.150.1-1 on Azure Linux 3.0 | — | Microsoft (MSRC) |
| azl3 kernel 6.6.152.1-1 on Azure Linux 3.0 | 6.6.157.1-1 · Release Notes | Microsoft (MSRC) |
| debian:linux | 6.1.190-1 · Debian:12 | Package registry (OSV) |
| debian:linux | 6.12.111-1 · Debian:13 | Package registry (OSV) |
| debian:linux-6.12 | 6.12.111-1~deb12u1 · Debian:12 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
National notice (Türkiye Cybersecurity Directorate / USOM)
Official security notices citing this record; remediation advice is on the agency's page.
- TR-26-1085 · Sep 14, 2026(Linux Kernel Güvenlik Bildirimi)
Technical details
Attack conditions
- Someone with local access to the system can trigger it.
- A low-privileged account is enough.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
—
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
- SSVC exploitation— → none
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (5 more)Show less
- git.kernel.org/stable/c/0926f59ca0f94120895b92180c636a48d0ed3a6d
- git.kernel.org/stable/c/6a644a7340df978785f3109d1e0726a982ce2c6f
- git.kernel.org/stable/c/c924884743e948e25625b7fbf3ee2a9325a204a7
- git.kernel.org/stable/c/dadd97c8296b23aa816e91ed70041820ae087baa
- git.kernel.org/stable/c/df441f3efbb50eb0f120b8de4bf441c31fb0551d
Vendor advisories and official records. Exploit/PoC links are deliberately left out.