CVE-2026-99064

HIGH

MEDIUM Priority: 0.04 BB Relevance: 66/100

Published: 2026-10-23 Modified: 2026-10-24 First seen: 2026-10-29 Status: active

Attack Surface

Network No Auth No Interaction Conf. Impact Integ. Impact

CVSS Vector Breakdown

AV: Network

AC: High

PR: None

UI: None

S: Unchanged

C: High

I: High

A: High

Description

In the Linux kernel, the following vulnerability has been resolved: cipso: adjust cached option offsets when removing CIPSO cipso_v4_skbuff_delattr() removes the CIPSO bytes but does not adjust cached offsets for options that follow them. For example, with a valid 10-byte CIPSO option followed by a seven-byte RR option, parsing records rr at offset 30. Removing CIPSO moves RR to offset 20, while the cached offset remains 30. Consumers such as ip_forward_options() and __ip_options_echo() then access the wrong bytes; the latter may interpret packet data as the option length and copy it into fixed-size option storage. Mirror cipso_v4_delopt() and subtract cipso_len from the srr, rr, ts and router_alert offsets when they follow CIPSO. cipso_len is the distance the first memmove() shifts those options. The later header move and network-header reset relocate the bytes and their offset base together.