CyberSecBulletin
CVE-2025-62514NVD status: Analyzed

parsec-cloud: Use of a Broken or Risky Cryptographic Algorithm

CVE-2025-62514 is a high-severity use of a broken or risky cryptographic algorithm vulnerability in parsec-cloud from Scille, with a CVSS 3.1 base score of 7.1 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected parsec-cloud versions: >= 3.0.0-alpha, < 3.6.0. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.3% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Parsec to 3.6.0 or a later version.
  2. Read the advisory on github.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
Scilleparsec-cloud>= 3.0.0-alpha, < 3.6.0Not stated
Parsec.cloudParsec3.0.0 up to, but not including, 3.6.03.6.0

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
HighSuccess depends on conditions outside the attacker's control.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
LowPerformance or availability is reduced.

Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:L. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.18.3HighCNA (github.com)
CVSS 3.17.1HighNVD

Official description

Parsec is a cloud-based application for cryptographically secure file sharing. In versions on the 3.x branch prior to 3.6.0, `libparsec_crypto`, a component of the Parsec application, does not check for weak order point of Curve25519 when compiled with its RustCrypto backend. In practice this means an attacker in a man-in-the-middle position would be able to provide weak order points to both parties in the Diffie-Hellman exchange, resulting in a high probability to for both parties to obtain the same shared key (hence leading to a successful SAS code exchange, misleading both parties into thinking no MITM has occurred) which is also known by the attacker. Note only Parsec web is impacted (as Parsec desktop uses `libparsec_crypto` with the libsodium backend). Version 3.6.0 of Parsec patches the issue.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Use of a Broken or Risky Cryptographic Algorithm

The product uses a broken or risky cryptographic algorithm or protocol.

How developers prevent this class of flaw

  • Ensure that the design allows one cryptographic algorithm to be replaced with another in the next generation or version. Where possible, use wrappers to make the interfaces uniform. This will make it easier to upgrade to stronger algorithms. With hardware, design the product at the Intellectual Property (IP) level so that one cryptographic algorithm can be replaced with another in the next generation of the hardware product.
  • Carefully manage and protect cryptographic keys (see CWE-320). If the keys can be guessed or stolen, then the strength of the cryptography itself is irrelevant.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Industry-standard implementations will save development time and may be more likely to avoid errors that can occur during implementation of cryptographic algorithms. Consider the ESAPI Encryption feature.

More Use of a Broken or Risky Cryptographic Algorithm vulnerabilities (CWE-327)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in parsec-cloud

All parsec-cloud vulnerabilities

Recent Use of a Broken or Risky Cryptographic Algorithm vulnerabilities

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