CyberSecBulletin
CVE-2022-36536NVD status: Modified

Syncovery: Use of Insufficiently Random Values

Published Updated By the CyberSecBulletin desk

CVE-2022-36536 is a critical-severity use of insufficiently random values vulnerability in Syncovery, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 9.48j as the first without the flaw, so updating Syncovery to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 4.85% chance of exploitation within 30 days, which is in the top 7.83% of all scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Update Syncovery to 9.48j or a later version.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
SyncoverySyncovery8.00 up to, but not including, 9.48j9.48j

Version data comes from NVD's product matching. 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
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
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
HighThe component can be taken down completely.

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

Official description

An issue in the component post_applogin.php of Super Flexible Software GmbH & Co. KG Syncovery 9 for Linux v9.47x and below allows attackers to escalate privileges via creating crafted session tokens.

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

The underlying weakness: Use of Insufficiently Random Values

The product uses insufficiently random numbers or values in a security context that depends on unpredictable numbers.

How developers prevent this class of flaw

  • Use a well-vetted algorithm that is currently considered to be strong by experts in the field, and select well-tested implementations with adequate length seeds. In general, if a pseudo-random number generator is not advertised as being cryptographically secure, then it is probably a statistical PRNG and should not be used in security-sensitive contexts. Pseudo-random number generators can produce predictable numbers if the generator is known and the seed can be guessed. A 256-bit seed is a good starting point for producing a random enough number.
  • Consider a PRNG that re-seeds itself as needed from high quality pseudo-random output sources, such as hardware devices.
  • Use products or modules that conform to FIPS 140-2 to avoid obvious entropy problems. Consult FIPS 140-2 Annex C (Approved Random Number Generators).

More Use of Insufficiently Random Values vulnerabilities (CWE-330)

Timeline

  1. CVE record published.
  2. Record last changed materially (score, affected products, status or references).

References

Technical write-ups (may include proof of concept)

Recent Use of Insufficiently Random Values vulnerabilities

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