CVSS3
Attack Vector
ADJACENT
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
NONE
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N
AI Score
Confidence
Low
EPSS
Percentile
15.5%
Users of IPsec transparent encryption in Cilium may be vulnerable to cryptographic attacks that render the transparent encryption ineffective.
In particular, Cilium is vulnerable to the following attacks by a man-in-the-middle attacker:
These attacks are possible due to an ESP sequence number collision when multiple nodes are configured with the same key. Fixed versions of Cilium use unique keys for each IPsec tunnel established between nodes, resolving all of the above attacks.
Important: After upgrading, users must perform a key rotation using the instructions here to ensure that they are no longer vulnerable to this issue. Please note that the key rotation instructions have recently been updated, and users must use the new instructions to properly establish secure IPsec tunnels. To validate that the new instructions have been followed properly, ensure that the IPsec Kubernetes secret contains a “+” sign.
All prior versions of Cilium that support IPsec transparent encryption (Cilium 1.4 onwards) are affected by this issue.
Patched versions:
There is no workaround to this issue. IPsec transparent encryption users are strongly encouraged to upgrade.
The Cilium community has worked together with members of Cure53 and Isovalent to prepare these mitigations. Special thanks to @NikAleksandrov and @pchaigno for their work on remediating the issue. Thanks to Marsh Ray, Senior Software Developer at Microsoft, for input and guidance on the fix.
If you have any questions or comments about this advisory, please reach out on Slack.
As usual, if you think you found a related vulnerability, we strongly encourage you to report security vulnerabilities to our private security mailing list: [email protected] - first, before disclosing them in any public forums. This is a private mailing list where only members of the Cilium internal security team are subscribed to, and is treated as top priority.
docs.cilium.io/en/stable/security/network/encryption-ipsec
github.com/advisories/GHSA-pwqm-x5x6-5586
github.com/cilium/cilium/commit/311fbce5280491cddceab178d83b06fa23688c72
github.com/cilium/cilium/commit/a1742b478306fa256cd27df1039dfae0537b4149
github.com/cilium/cilium/commit/a652c123331852cca90c74202f993d4170fd37fa
github.com/cilium/cilium/security/advisories/GHSA-pwqm-x5x6-5586
nvd.nist.gov/vuln/detail/CVE-2024-28860
pkg.go.dev/vuln/GO-2024-2666