Skip to content
Noroxi
NVD / CVE Program· CNA Linux

CVE-2026-72393: eth: fbnic: don't cache shinfo across skb realloc

Noroxi assessment

Priority: Monitor (action score 39/100)

  • 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: 0.63% (FIRST EPSS); higher than 50.6% of all records.
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Linux Linux 21f304c2aae46625e050c28d979f4b9d83faa85e, 62b68b774f06bf52e329f254f0199bc43d350ccf, 83df3e2594cd78aa40b1246a19879abb4891945b.

Low priority for now. Upgrade to Linux Linux 21f304c2aae46625e050c28d979f4b9d83faa85e, 62b68b774f06bf52e329f254f0199bc43d350ccf, 83df3e2594cd78aa40b1246a19879abb4891945b 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: eth: fbnic: don't cache shinfo across skb realloc fbnic_tx_lso() calls skb_cow_head() which may reallocate the skb including the shared info. We can't use the pointer calculated before the call. BUG: KASAN: slab-use-after-free in fbnic_tx_lso.isra.0+0x668/0x8e0 Read of size 4 at addr ff110000262edd98 by task swapper/5/0 Call Trace: fbnic_tx_lso.isra.0+0x668/0x8e0 fbnic_xmit_frame+0x622/0xba0 dev_hard_start_xmit+0xf4/0x620 Allocated by task 8653: __alloc_skb+0x11e/0x5f0 alloc_skb_with_frags+0xcc/0x6c0 sock_alloc_send_pskb+0x327/0x3f0 __ip_append_data+0x188b/0x47a0 ip_make_skb+0x24a/0x300 udp_sendmsg+0x14d2/0x21e0 Freed by task 0: kfree+0x123/0x5a0 pskb_expand_head+0x36c/0xfa0 fbnic_tx_lso.isra.0+0x500/0x8e0 fbnic_xmit_frame+0x622/0xba0 dev_hard_start_xmit+0xf4/0x620 sch_direct_xmit+0x25b/0x1100 The buggy address belongs to the object at ff110000262edc40 which belongs to the cache skbuff_small_head of size 640 The buggy address is located 344 bytes inside of freed 640-byte region [ff110000262edc40, ff110000262ede

CriticalCVSS 9.8 · v3.1—No exploit Fix available
Published
Aug 15, 2026
Updated
Aug 17, 2026
EPSS
0.6% · 50th percentile
CWE
—

Report tools

JSON

Action score

39

Monitor

Low priority for now.

CVSS
39 / 40 · 9.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.6%

CNA vs NVD score

NVD
—
CNA · Linux
9.8
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.

Follow CVE-2026-72393

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

One daily email digest (06:00 UTC); connect a webhook for KEV listings and weaponized exploits instantly.

Your free account also gets you

  • Stack alerts: add the products and versions you run, get the new CVEs that affect them
  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools (3 a day without an account), an API key and MCP
  • All your scans in one panel: findings, what changed in the last scan, a report per domain or per client (PDF, share link)
All free tools

Sign up with email · Have an account? Sign in

Free account, no card. Unfollow any time.

Don't want an account? Get "Exploited this week" by email every MondayDon't want an account? RSS feed for linux records
Is your version affected? Check it

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 help

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

    • 6.15affected
    • b0b0f52042acb324cd39fbefb2b1ae83af8f8ae1 and later · before 83df3e2594cd78aa40b1246a19879abb4891945baffected · git
    • b0b0f52042acb324cd39fbefb2b1ae83af8f8ae1 and later · before 21f304c2aae46625e050c28d979f4b9d83faa85eaffected · git
    • b0b0f52042acb324cd39fbefb2b1ae83af8f8ae1 and later · before 62b68b774f06bf52e329f254f0199bc43d350ccfaffected · git
    • before 6.15not affected · semver
    • 6.18.40 and later · up to and including 6.18.*not affected · semver
    • 7.1.5 and later · up to and including 7.1.*not affected · semver
    • 7.2 and laternot affected · original_commit_for_fix

Package-level exposure

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

EcosystemPackageAffected rangeFix
Debian:14linuxbefore 7.1.5-17.1.5-1

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-2026-72387Aug 15, 2026 · drm/panthor: Fix potential invalid pointer deref in group_process_tiler_oom()
    0Monitor
  • ← EarlierCVE-2026-72391Aug 15, 2026 · net: phy: sfp: free mii_bus in sfp_i2c_mdiobus_destroy
    0Monitor
  • Later →CVE-2026-72394Aug 15, 2026 · hwmon: (aspeed-g6-pwm-tach) Guard fan RPM calculation against divide-by-zero
    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 / packageFixed versionSource
Linux Linux21f304c2aae46625e050c28d979f4b9d83faa85eVendor (CNA)
Linux Linux62b68b774f06bf52e329f254f0199bc43d350ccfVendor (CNA)
Linux Linux83df3e2594cd78aa40b1246a19879abb4891945bVendor (CNA)
debian:linux7.1.5-1 · Debian:14Package 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.

EPSS, last 120 days

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 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.

—

Bug bounty scope

No known public program.

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

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • 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
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

—

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/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

  1. Fix✗ → ✓

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

References

Show all references (2 more)

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

All records