GHSA-434v-x5qv-pmh6
libcrux has All-Zero Key Generation Upon Catastrophic RNG Failure
The libcrux-ed25519 key generation samples Ed25519 secret keys from a provided CSPRNG in a loop for up to 100 attempts until a non-zero key is found. If a non-zero key could not be sampled within 100 attempts the key generation function would silently continue with an all-zero buffer as the secret key.
Impact
This bug only occurs in the event of a catastrophic failure of the CSPRNG, but would allow anyone to forge signatures under the resulting static signing key.
Mitigation
Instead of silently continuing with an all-zero signing key, starting from version 0.0.7 key generation will error in the case of 100 failed attempts at sampling a valid key.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- High
- Availability
- None
What each source reports
GitHub Advisories Score used
libcrux has All-Zero Key Generation Upon Catastrophic RNG Failure
The libcrux-ed25519 key generation samples Ed25519 secret keys from a provided CSPRNG in a loop for up to 100 attempts until a non-zero key is found. If a non-zero key could not be sampled within 100 attempts the key generation function would silently continue with an all-zero buffer as the secret key.
Impact
This bug only occurs in the event of a catastrophic failure of the CSPRNG, but would allow anyone to forge signatures under the resulting static signing key.
Mitigation
Instead of silently continuing with an all-zero signing key, starting from version 0.0.7 key generation will error in the case of 100 failed attempts at sampling a valid key.
- Record
GHSA-434v-x5qv-pmh6- CVSS 4.0
- 8.2 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-331, CWE-392, CWE-1240
- Updated
- 2026-11-02
OSV
libcrux has All-Zero Key Generation Upon Catastrophic RNG Failure
The libcrux-ed25519 key generation samples Ed25519 secret keys from a provided CSPRNG in a loop for up to 100 attempts until a non-zero key is found. If a non-zero key could not be sampled within 100 attempts the key generation function would silently continue with an all-zero buffer as the secret key.
Impact
This bug only occurs in the event of a catastrophic failure of the CSPRNG, but would allow anyone to forge signatures under the resulting static signing key.
Mitigation
Instead of silently continuing with an all-zero signing key, starting from version 0.0.7 key generation will error in the case of 100 failed attempts at sampling a valid key.
- Record
GHSA-434v-x5qv-pmh6- CVSS 4.0
- 8.2 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-1240, CWE-331, CWE-392
- Updated
- 2026-11-02
OSVRUSTSEC-2026-0075
All-Zero Key Generation on Catastrophic RNG Failure
The libcrux-ed25519 key generation samples Ed25519 secret keys from a provided CSPRNG in a loop for up to 100 attempts until a non-zero key is found. If a non-zero key could not be sampled within 100 attempts the key generation function would silently continue with an all-zero buffer as the secret key.
Impact
This bug only occurs in the event of a catastrophic failure of the CSPRNG, but would allow anyone to forge signatures under the resulting static signing key.
Mitigation
Instead of silently continuing with an all-zero signing key, starting
from version 0.0.7 key generation will error in the case of 100
failed attempts at sampling a valid key.
- Record
RUSTSEC-2026-0075- CVSS 4.0
- 8.2 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N - Updated
- 2026-11-02
Affected packages
| Package | Affected | Fixed |
|---|---|---|
libcrux-ed25519crates.io | before 0.0.7 | 0.0.7 |
libcrux-ed25519crates.io | 0.0.0-0 up to 0.0.7 | 0.0.7 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | GitHub Advisories, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
GHSA-434v-x5qv-pmh6 is a high vulnerability (CVSS 8.2) in libcrux-ed25519, published March 4, 2026. No source lists public exploit code. Fixed in libcrux-ed25519 0.0.7.