Critical severity · published Jul 19, 2026
CVE-2026-64055
net: ethernet: cortina: Carry over frag counter
9.8
CVSS
0.5%
EPSS
No
On KEV
Description
In the Linux kernel, the following vulnerability has been resolved:
net: ethernet: cortina: Carry over frag counter
The gmac_rx() NAPI poll function assembles packets in an
SKB from a ring buffer.
If the ring buffer gets completely emptied during a poll cycle,
we exit gmac_rx(), but the packet is not yet completely
assembled in the SKB, yet the fragment counter frag_nr is
reset to zero on the next invocation.
Solve this by making the RX fragment counter a part of the
port struct, and carry it over between invocations.
Reset the fragment counter only right after calling
napi_gro_frags(), on error (after calling napi_free_frags())
or if stopping the port.
Reset it in some place where not strictly necessary just to
emphasize what is going on.
This was found by Sashiko during normal patch review.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 44% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
4.16 before 5.10.258; 5.11 before 5.15.209; 5.16 before 6.1.175; 6.2 before 6.6.142; 6.7 before 6.12.92; 6.13 before 6.18.34; +4 more · source: NVD
LI
Linux · Linux
4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 before df31e3b64455293df1ea89c7da7d5c9bfbcdd253; 4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 before 7af1fabdee744b7995fe01b30b77dfc397657cb5; 4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 before 75105fcf73f1ce7d9f769aaefec6e6d6645d5ac0; 4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 before 78cf08b3be47c28f07008a76c932bad7cdffa9d8; 4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 before 7123cf481e21b54eb6adc4cb0d8dc2876aeaee41; 4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 before c373b34877afea61c89e0dd2e38948c624249b9b; +3 more · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-64055
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-64055
Patch
https://git.kernel.org/stable/c/46806096f35b8d3dfa2f321ddd77f597edcdb85f
Patch
https://git.kernel.org/stable/c/7123cf481e21b54eb6adc4cb0d8dc2876aeaee41
Patch
https://git.kernel.org/stable/c/75105fcf73f1ce7d9f769aaefec6e6d6645d5ac0
Patch
https://git.kernel.org/stable/c/78cf08b3be47c28f07008a76c932bad7cdffa9d8
Patch
https://git.kernel.org/stable/c/7af1fabdee744b7995fe01b30b77dfc397657cb5
Patch
https://git.kernel.org/stable/c/c373b34877afea61c89e0dd2e38948c624249b9b
More from Kernel
9.8
CVE-2025-39682
tls: fix handling of zero-length records on the rx_list
8.8
CVE-2026-53266
netfilter: bridge: make ebt_snat ARP rewrite writable
8.8
CVE-2013-6282
Linux Kernel Improper Input Validation Vulnerability
8.4
CVE-2022-0185
Linux Kernel Heap-Based Buffer Overflow Vulnerability
8.4
CVE-2013-2094
Linux Kernel Privilege Escalation Vulnerability
