What’s Vulnerable › Vulnerabilities

CVE-2023-38710

• Severity: medium (CVSS 6.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.8% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2023-08-25 · updated 2026-06-17

Description

An issue was discovered in Libreswan before 4.12. When an IKEv2 Child SA REKEY packet contains an invalid IPsec protocol ID number of 0 or 1, an error notify INVALID_SPI is sent back. The notify payload's protocol ID is copied from the incoming packet, but the code that verifies outgoing packets fails an assertion that the protocol ID must be ESP (2) or AH(3) and causes the pluto daemon to crash and restart. NOTE: the earliest affected version is 3.20.

Affected products

• The Libreswan Project libreswan: from 3.20 before 4.12 — fixed in 4.12

How to fix

Upgrade to a fixed version: The Libreswan Project libreswan 4.12. Check the vendor advisory for mitigations.

References

• https://github.com/libreswan/libreswan/tags
• https://libreswan.org/security/CVE-2023-38710/
• https://github.com/libreswan/libreswan/tags
• https://libreswan.org/security/CVE-2023-38710/

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