CyberSecBulletin
CVE-2022-35925NVD status: Modified

bookwyrm: Improper Restriction of Excessive Authentication Attempts

CVE-2022-35925 is a critical-severity improper restriction of excessive authentication attempts vulnerability in bookwyrm from Bookwyrm-social, 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 bookwyrm versions: < 0.4.5. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.79% chance of exploitation within 30 days, higher than 79% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of bookwyrm you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Bookwyrm-socialbookwyrm< 0.4.5Not 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
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.

Scoring systemScoreSeverityScored by
CVSS 3.15.3MediumCNA (github.com)
CVSS 3.19.8CriticalNVD

Official description

BookWyrm is a social network for tracking reading. Versions prior to 0.4.5 were found to lack rate limiting on authentication views which allows brute-force attacks. This issue has been patched in version 0.4.5. Admins with existing instances will need to update their `nginx.conf` file that was created when the instance was set up. Users are advised advised to upgrade. Users unable to upgrade may update their nginx.conf files with the changes manually.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Restriction of Excessive Authentication Attempts

The product does not implement sufficient measures to prevent multiple failed authentication attempts within a short time frame.

How developers prevent this class of flaw

  • Common protection mechanisms include: Disconnecting the user after a small number of failed attempts Implementing a timeout Locking out a targeted account Requiring a computational task on the user's part.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Consider using libraries with authentication capabilities such as OpenSSL or the ESAPI Authenticator.

More Improper Restriction of Excessive Authentication Attempts vulnerabilities (CWE-307)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Technical write-ups (may include proof of concept)

Other vulnerabilities in bookwyrm

All bookwyrm vulnerabilities

Recent Improper Restriction of Excessive Authentication Attempts vulnerabilities

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