CVE-2026-65630 potatosalad CVE debrief

Who should care

Defenders responsible for systems and applications using jose versions between 1.10.0 and 1.11.12 should assess exposure and prioritize remediation. This includes operators, platform administrators, vulnerability management teams, and security teams who need to verify their inventory of systems and applications using affected jose versions and update to a fixed version.

Why it matters

CVE-2026-65630 is a timing side-channel vulnerability in the jose library that allows recovery of a long-term X25519 private key. Defenders should prioritize verifying their inventory of systems and applications using affected jose versions and update to a fixed version.

• Key recovery could compromise confidentiality and authenticity of data protected by the affected key
• Defenders must verify their inventory and update to a fixed version to prevent potential key recovery

Technical summary

The jose library is vulnerable to a timing side-channel attack, allowing an attacker to recover a long-term X25519 private key through measurement of decryption timing for attacker-supplied ECDH-ES (JWE) messages. The vulnerability affects jose versions from 1.10.0 before 1.11.13. The pure-Erlang X25519 implementation performs scalar multiplication over the secret private key using a recursive Montgomery ladder whose clauses branch on individual bits of the clamped private scalar. The execution time of the public entry points is thus a function of the private key. An attacker who can submit ciphertexts and measure decryption timing can, in principle, recover the private key bit by bit, defeating the resistance.

Defensive priority

Defenders should prioritize verifying their inventory of systems and applications using jose versions between 1.10.0 and 1.11.12, and updating to version 1.11.13 or later. Compensating controls, such as monitoring for suspicious decryption timing, may be necessary until remediation can be completed.

Recommended defensive actions

• Verify inventory of systems and applications using jose versions between 1.10.0 and 1.11.12
• Update jose to version 1.11.13 or later
• Monitor for suspicious decryption timing
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, including its description, CVSS score, and affected versions. Additional information is available from the Erlang/OTP Security Advisories and other source references.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.