LibreOffice: Use of Insufficiently Random Values
CVE-2022-26306 is a high-severity use of insufficiently random values vulnerability in LibreOffice from The Document Foundation, 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. The record lists versions 7.2.7, 7.3.1 as the first without the flaw, so updating LibreOffice to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 1.13% chance of exploitation within 30 days, higher than 67% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update LibreOffice to 7.2.7 or 7.3.1, whichever matches your release line, or a later version.
- Read the advisory on libreoffice.org 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 |
|---|---|---|---|
| The Document Foundation | LibreOffice | 7.2 up to, but not including, 7.2.7; 7.3 up to, but not including, 7.3.1 | 7.2.7, 7.3.1 |
| Debian | Debian Linux | 10.0 | 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 NVD.
Official description
LibreOffice supports the storage of passwords for web connections in the user’s configuration database. The stored passwords are encrypted with a single master key provided by the user. A flaw in LibreOffice existed where the required initialization vector for encryption was always the same which weakens the security of the encryption making them vulnerable if an attacker has access to the user's configuration data. This issue affects: The Document Foundation LibreOffice 7.2 versions prior to 7.2.7; 7.3 versions prior to 7.3.1.
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.
- Record last changed materially (score, affected products, status or references).
References
Third-party and government advisories
- openwall.com/lists/oss-security/2022/08/13/1Mailing List, Third Party Advisory
- lists.debian.org/debian-lts-announce/2023/03/msg00022.htmlMailing List, Third Party Advisory
Other vulnerabilities in LibreOffice
- 8.5 High severity
- 7.8 High severity
- 7.3 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
Recent Use of Insufficiently Random Values vulnerabilities
- 7.5 High severity
- 9.8 Critical severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 9.8 Critical severity
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