Totd: Insufficient Entropy
CVE-2022-34294 is a critical-severity insufficient entropy vulnerability in Totd from Totd Project, 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. Affected Totd versions: 1.5.3. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.9% chance of exploitation within 30 days, higher than 80% of scored CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of Totd you run against the affected versions below, and install the vendor's latest release.
- 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 |
|---|---|---|---|
| Totd Project | Totd | 1.5.3 | Not stated |
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
totd 1.5.3 uses a fixed UDP source port in upstream queries sent to DNS resolvers. This allows DNS cache poisoning because there is not enough entropy to prevent traffic injection attacks.
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.
- Record last changed materially (score, affected products, status or references).
References
Third-party and government advisories
- github.com/fwdillema/totdThird Party Advisory
- blackhat.com/presentations/bh-jp-08/bh-jp-08-Kaminsky/BlackHat-Japan-08-Kaminsky-DNS08-BlackOps.pdfThird Party Advisory
- usenix.org/conference/usenixsecurity22/presentation/jeitnerTechnical Description, Third Party Advisory
Technical write-ups (may include proof of concept)
- openwall.com/lists/oss-security/2022/08/14/2Exploit, Mailing List, Third Party Advisory
Recent Insufficient Entropy vulnerabilities
- 8.8 High severity
- 8.1 High severity
- 7.5 High severity
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