chamilo-lms: Use of Insufficiently Random Values
CVE-2026-33710 is a high-severity use of insufficiently random values vulnerability in chamilo-lms from Chamilo, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected chamilo-lms versions: < 1.11.38; >= 2.0.0-alpha.1, < 2.0.0-RC.3. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.29% 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
- Check which version of chamilo-lms you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Chamilo | chamilo-lms | < 1.11.38; >= 2.0.0-alpha.1, < 2.0.0-RC.3 | Not stated |
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
- 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
- NoneNothing can be modified.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N. Scored by CNA (github.com).
Official description
Chamilo LMS is a learning management system. Prior to 1.11.38 and 2.0.0-RC.3, REST API keys are generated using md5(time() + (user_id * 5) - rand(10000, 10000)). The rand(10000, 10000) call always returns exactly 10000 (min == max), making the formula effectively md5(timestamp + user_id*5 - 10000). An attacker who knows a username and approximate key creation time can brute-force the API key. This vulnerability is fixed in 1.11.38 and 2.0.0-RC.3.
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: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other vulnerabilities in chamilo-lms
- 7.2 High severity
- 7.5 High severity
- 8.9 High severity
- 9.0 Critical severity
- 9.8 Critical severity
- 9.3 Critical severity
Recent Use of Insufficiently Random Values vulnerabilities
- 9.8 Critical severity
- 8.6 High severity
- 9.8 Critical severity
- 9.8 Critical severity
- 7.5 High severity
- 9.1 Critical severity
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