CVE-2026-99064
Received
Received - Intake
Memory Corruption in Linux Kernel CIPSO Option Handling
Vulnerability report for CVE-2026-99064, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-10-23
Last updated on: 2026-10-23
Assigner: kernel.org
Description
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.
CVSS Scores
EPSS Scores
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Meta Information
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |