CVE Intelligence
Critical

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

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

Published Aug 15, 2026 · Updated Oct 15, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: Linux

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • Technical severity (critical)+10

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
—
No EPSS score.
Affects
Linux
Linux
CVSS base
9.8
Critical · 2 source(s)

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
  2. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  3. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  4. Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Linux Linux ≥ b0b0f52042acb324cd39fbefb2b1ae83af8f8ae1 and < 83df3e2594cd78aa40b1246a19879abb4891945b≥ b0b0f52042acb324cd39fbefb2b1ae83af8f8ae1 and < 21f304c2aae46625e050c28d979f4b9d83faa85e≥ b0b0f52042acb324cd39fbefb2b1ae83af8f8ae1 and < 62b68b774f06bf52e329f254f0199bc43d350ccfversion 6.15 Vulnerable CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
9.8 CVSS 3.1 Critical 3.9 5.9 416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database
9.8 CVSS 3.1 Critical — — Linux via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H (score shown at the top: 416baaa9-dc9f-4396-8d5f-8c081fb06d67)

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
web/proxy/WAF logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · linux/linux
    Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 15, 2026
  • CVSS changed · 9.8
    Oct 15, 2026 · NIST National Vulnerability Database
  • Source status changed · → Received
    Oct 15, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 15, 2026 · NIST National Vulnerability Database
  • CVE published
    Aug 15, 2026 · Linux

Source activity

Repeated readings are counted rather than listed.

  • 1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

3 on the record

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

  • Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 14h
  • Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 14h
  • Unknown CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 1d
  • Unknown CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 1d
  • Unknown CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 1d
  • Unknown CVE-2026-98427 net/sched: codel: bound the dropping loop per dequeue call 1d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No FIRST EPSS score.
  • No fixed version, patch or mitigation documented.
  • No CISA SSVC assessment.
  • No CWE classification.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-72393 is "eth: fbnic: don't cache shinfo across skb realloc", rated Critical. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 9.8 describes technical severity. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

Comments

Moderated technical discussion. Read the community guidelines.

No comments yet.

Sign in or create an account to comment and suggest corrections.