Juju: Use of Insufficiently Random Values
CVE-2024-7558 is a high-severity use of insufficiently random values vulnerability in Juju from Canonical, with a CVSS 3.1 base score of 8.0 out of 10. It can be exploited from the same local network by an attacker with a low-privileged account, without any action from a user. The record lists versions 3.5.4, 3.4.6, 3.3.7 as the first without the flaw, so updating Juju to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.5% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Juju to 3.5.4 or 3.4.6 or 3.3.7 or 3.1.10, whichever matches your release line, or a later version.
- Read the advisory on github.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Canonical | Juju | 3.5 up to, but not including, 3.5.4; 3.4 up to, but not including, 3.4.6; 3.3 up to, but not including, 3.3.7; 3.1 up to, but not including, 3.1.10; 2.9 up to, but not including, 2.9.51 | 3.5.4, 3.4.6, 3.3.7, 3.1.10, 2.9.51 |
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
- AdjacentThe attacker must be on the same local network segment.
- 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:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 8.7 | High | CNA (ubuntu.com) |
| CVSS 3.1 | 8.0 | High | NVD |
Official description
JUJU_CONTEXT_ID is a predictable authentication secret. On a Juju machine (non-Kubernetes) or Juju charm container (on Kubernetes), an unprivileged user in the same network namespace can connect to an abstract domain socket and guess the JUJU_CONTEXT_ID value. This gives the unprivileged user access to the same information and tools as the Juju charm.
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
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Third-party and government advisories
- cve.org/CVERecord?id=CVE-2024-7558Third Party Advisory
Other vulnerabilities in Juju
- 7.1 High severity
- 10.0 Critical severity
- 8.8 High severity
- 8.8 High severity
Recent Use of Insufficiently Random Values vulnerabilities
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 9.8 Critical severity
- 8.2 High severity
- 8.1 High severity
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