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NVD / CVE Program· CNA Linux

CVE-2025-40268: cifs: client: fix memory leak in smb3_fs_context_parse_param

Noroxi assessment

Priority: Monitor (action score 0/100)

  • 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: 0.20% (FIRST EPSS).
  • Fixed version: Linux Linux 299bc05e1475a4aa1eb985ade8f39e68c1bba9b9, 4515743cc7a42e1d67468402a6420c195532a6fa, 48c17341577e25a22feb13d694374b61d974edbc; azl3 kernel 6.6.112.1-2 on Azure Linux 3.0 6.6.117.1-1.

Low priority for now. Upgrade to Linux Linux 299bc05e1475a4aa1eb985ade8f39e68c1bba9b9, 4515743cc7a42e1d67468402a6420c195532a6fa, 48c17341577e25a22feb13d694374b61d974edbc; azl3 kernel 6.6.112.1-2 on Azure Linux 3.0 6.6.117.1-1 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: cifs: client: fix memory leak in smb3_fs_context_parse_param The user calls fsconfig twice, but when the program exits, free() only frees ctx->source for the second fsconfig, not the first. Regarding fc->source, there is no code in the fs context related to its memory reclamation. To fix this memory leak, release the source memory corresponding to ctx or fc before each parsing. syzbot reported: BUG: memory leak unreferenced object 0xffff888128afa360 (size 96): backtrace (crc 79c9c7ba): kstrdup+0x3c/0x80 mm/util.c:84 smb3_fs_context_parse_param+0x229b/0x36c0 fs/smb/client/fs_context.c:1444 BUG: memory leak unreferenced object 0xffff888112c7d900 (size 96): backtrace (crc 79c9c7ba): smb3_fs_context_fullpath+0x70/0x1b0 fs/smb/client/fs_context.c:629 smb3_fs_context_parse_param+0x2266/0x36c0 fs/smb/client/fs_context.c:1438

—No exploit Fix available
Published
Dec 6, 2025
Updated
Oct 30, 2026
EPSS
0.2% · 10th percentile
CWE
—

Report tools

JSON

Action score

0

Monitor

Low priority for now.

CVSS
0 / 40 · —
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.2%

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  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

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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.

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Affected 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

    • 5.11affected
    • af1a3d2ba9543e99d78914d8fb88b61d0531d9a1 and later · before 299bc05e1475a4aa1eb985ade8f39e68c1bba9b9affected · git
    • af1a3d2ba9543e99d78914d8fb88b61d0531d9a1 and later · before 868fc62811d3fabcf5685e14f36377a855d5412daffected · git
    • af1a3d2ba9543e99d78914d8fb88b61d0531d9a1 and later · before 48c17341577e25a22feb13d694374b61d974edbcaffected · git
    • af1a3d2ba9543e99d78914d8fb88b61d0531d9a1 and later · before 4515743cc7a42e1d67468402a6420c195532a6faaffected · git
    • af1a3d2ba9543e99d78914d8fb88b61d0531d9a1 and later · before e8c73eb7db0a498cd4b22d2819e6ab1a6f506bd6affected · git
    • before 5.11not affected · semver
    • 6.1.191 and later · up to and including 6.1.*not affected · semver
    • 6.6.117 and later · up to and including 6.6.*not affected · semver
    • 6.12.59 and later · up to and including 6.12.*not affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12linuxfrom 0—
Debian:13linuxbefore 6.12.63-16.12.63-1
Debian:14linuxbefore 6.17.9-16.17.9-1

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-74705udp: fix potential use-after-free in tunnel segmentation
    40Plan
  • CVE-2026-74612veth: fix skb length accounting after XDP frag adjustment
    40Plan
  • CVE-2026-74475vxlan: use neigh_ha_snapshot() in route_shortcircuit()
    40Plan

Published before and after this one in the same product

  • ← EarlierCVE-2025-40280Dec 6, 2025 · tipc: Fix use-after-free in tipc_mon_reinit_self().
    31Monitor
  • ← EarlierCVE-2025-40267Dec 6, 2025 · io_uring/rw: ensure allocated iovec gets cleared for early failure
    0Monitor
  • Later →CVE-2025-40269Dec 6, 2025 · ALSA: usb-audio: Fix potential overflow of PCM transfer buffer
    31Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Linux Linux299bc05e1475a4aa1eb985ade8f39e68c1bba9b9Vendor (CNA)
Linux Linux4515743cc7a42e1d67468402a6420c195532a6faVendor (CNA)
Linux Linux48c17341577e25a22feb13d694374b61d974edbcVendor (CNA)
Linux Linux868fc62811d3fabcf5685e14f36377a855d5412dVendor (CNA)
Linux Linuxe8c73eb7db0a498cd4b22d2819e6ab1a6f506bd6Vendor (CNA)
azl3 kernel 6.6.112.1-2 on Azure Linux 3.06.6.117.1-1 · CBL-Mariner ReleasesMicrosoft (MSRC)
debian:linux6.12.63-1 · Debian:13Package 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.

No history yet (it accumulates with the daily EPSS job).

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 researchers

Finders, 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.

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Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

No CVSS vector for this record, so attack conditions can't be derived.

Weakness class (CWE)

—

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

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (4 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records