LangBot: Insufficient Entropy
CVE-2026-90562 is a high-severity insufficient entropy vulnerability in LangBot from Langbot-app, with a CVSS 3.1 base score of 8.1 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 4.10.11 as the first without the flaw, so updating LangBot to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.73% chance of exploitation within 30 days, higher than 55% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update LangBot to 4.10.11 or a later version.
- 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 |
|---|---|---|---|
| Langbot-app | LangBot | 4.0.8.1 up to, but not including, 4.10.11 | 4.10.11 |
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
- 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:H/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (vulncheck.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 9.2 | Critical | CNA (vulncheck.com) |
| CVSS 3.1 | 8.1 | High | CNA (vulncheck.com) |
Official description
LangBot before 4.10.11 generates password recovery keys with only 24 bits of entropy and applies no rate limiting to the unauthenticated reset-password endpoint. Remote attackers knowing the administrator email can exhaust the keyspace through concurrent requests to reset the admin password and gain account access.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Insufficient Entropy
The product uses an algorithm or scheme that produces insufficient entropy, leaving patterns or clusters of values that are more likely to occur than others.
How developers prevent this class of flaw
- Determine the necessary entropy to adequately provide for randomness and predictability. This can be achieved by increasing the number of bits of objects such as keys and seeds.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other references
- github.com/langbot-app/LangBot
- github.com/langbot-app/LangBot/blob/v4.10.2/src/langbot/pkg/api/http/controller/groups/user.py
- github.com/langbot-app/LangBot/blob/v4.10.2/src/langbot/pkg/core/stages/genkeys.py
- github.com/langbot-app/LangBot/issues/2392
- vulncheck.com/advisories/langbot-before-4.10.11-authentication-bypass-via-weak-recovery-key
Other vulnerabilities in LangBot
- 8.6 High severity
- 8.8 High severity
- 8.6 High severity
Recent Insufficient Entropy vulnerabilities
- 7.4 High severity
- 9.0 Critical severity
- 7.5 High severity
- 7.5 High severity
- 7.1 High severity
- 7.5 High severity
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