Secret reconstruction via data-dependent modular multiplication
Published May 13, 2026 · Updated May 13, 2026
Observable timing discrepancy in PyQuorum before 0.2.1 allows remote attackers to recover secret shares through timed operations. The mul_mod function branches within a binary-expansion loop on each bit of its second operand, making runtime track the operand's Hamming weight. Exploitation requires repeated timing measurements of secret-sharing operations, and recovered share values enable reconstruction of the protected secret.
Summary
What happened
Observable timing discrepancy in PyQuorum before 0.2.1 allows remote attackers to recover secret shares through timed operations. The mul_mod function branches within a binary-expansion loop on each bit of its second operand, making runtime track the operand's Hamming weight. Exploitation requires repeated timing measurements of secret-sharing operations, and recovered share values enable reconstruction of the protected secret.
The record
- CVE
- CVE-2026-44368
- Published
- May 13, 2026
- Updated
- May 13, 2026
- Vendor
- svvqt
- Product
- PyQuorum
- Classifications
- CWE-208
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 13, 2026CVE publishedPublication date reported by the CVE source.
- May 13, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 0.2.1
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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