Vulnerability in Linux
CVE-2026-68119
In the Linux kernel, the following vulnerability has been resolved: tcp: initialize standalone TCP-AO response padding tcp_v4_send_ack() and tcp_v6_send_response() construct standalone TCP responses with TCP-AO options. The option length carries the actual MAC length, but the TCP header length includes the option rounded up to a four-byte boundary. tcp_ao_hash_hdr() writes the MAC only. Thus, when the MAC length is not four-byte aligned, the one to three bytes after the MAC are left uninitialized and may be transmitted. For the normal TCP-AO hashing mode, those bytes also have to be initialized before computing the MAC. Initialize only the alignment padding in the TCP-AO branches, before hashing the header. Use TCPOPT_NOP, as in the normal TCP-AO output path. This avoids adding work to non-AO TCP responses while preserving a valid authenticated header.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.004 (31.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 31st percentile — 31.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Linux — versions 7.1.6, 7.2, 6.7
References
Frequently asked questions
- What is CVE-2026-68119?
- CVE-2026-68119 is a high-severity vulnerability in Linux. CVSS score: 7.5/10. Published 2026-08-10.
- How severe is CVE-2026-68119?
- High severity. CVSS v3 base score is 7.5 out of 10.