CyberSecBulletin
CVE-2022-24756NVD status: Modified

bareos: Missing Release of Memory after Effective Lifetime

CVE-2022-24756 is a high-severity missing release of memory after effective lifetime vulnerability in bareos, 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 bareos versions: >= 18.2, < 19.2.12; >= 20.0.0, < 20.0.6; >= 21.0.0, < 21.1.0. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.93% chance of exploitation within 30 days, higher than 80% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of bareos 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
Bareosbareos>= 18.2, < 19.2.12; >= 20.0.0, < 20.0.6; >= 21.0.0, < 21.1.0Not 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
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.5HighCNA (github.com)
CVSS 3.17.5HighNVD
CVSS 2.04.3MediumNVD

Official description

Bareos is open source software for backup, archiving, and recovery of data for operating systems. When Bareos Director >= 18.2 but prior to 21.1.0, 20.0.6, and 19.2.12 is built and configured for PAM authentication, a failed PAM authentication will leak a small amount of memory. An attacker that is able to use the PAM Console (i.e. by knowing the shared secret or via the WebUI) can flood the Director with failing login attempts which will eventually lead to an out-of-memory condition in which the Director will not work anymore. Bareos Director versions 21.1.0, 20.0.6 and 19.2.12 contain a Bugfix for this problem. Users who are unable to upgrade may disable PAM authentication as a workaround.

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

The underlying weakness: Missing Release of Memory after Effective Lifetime

The product does not sufficiently track and release allocated memory after it has been used, making the memory unavailable for reallocation and reuse.

How developers prevent this class of flaw

  • Choose a language or tool that provides automatic memory management, or makes manual memory management less error-prone. For example, glibc in Linux provides protection against free of invalid pointers. When using Xcode to target OS X or iOS, enable automatic reference counting (ARC). To help correctly and consistently manage memory when programming in C++, consider using a smart pointer class such as std
  • Use an abstraction library to abstract away risky APIs. Not a complete solution.
  • Consider using the Boehm-Demers-Weiser garbage collector (bdwgc), which can help avoid leaks.

More Missing Release of Memory after Effective Lifetime vulnerabilities (CWE-401)

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

Patches and release notes

Other vulnerabilities in bareos

All bareos vulnerabilities

Recent Missing Release of Memory after Effective Lifetime vulnerabilities

Spotted an error? Tell us.