CyberSecBulletin
CVE-2022-40299NVD status: Modified

Singular: Use of Insufficiently Random Values

Published Updated By the CyberSecBulletin desk

CVE-2022-40299 is a high-severity use of insufficiently random values vulnerability in Singular, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists version 4.3.1 as the first without the flaw, so updating Singular to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.34% 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 Singular to 4.3.1 or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
SingularSingularbefore 4.3.14.3.1

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
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
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
HighThe component can be taken down completely.

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

Official description

In Singular before 4.3.1, a predictable /tmp pathname is used (e.g., by sdb.cc), which allows local users to gain the privileges of other users via a procedure in a file under /tmp. NOTE: this CVE Record is about sdb.cc and similar files in the Singular interface that have predictable /tmp pathnames; this CVE Record is not about the lack of a safe temporary-file creation capability in the Singular language.

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

Patches and release notes

Technical write-ups (may include proof of concept)

Recent Use of Insufficiently Random Values vulnerabilities

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