CyberSecBulletin
CVE-2022-23596NVD status: Modified

Junrar: Loop with Unreachable Exit Condition

CVE-2022-23596 is a high-severity loop with unreachable exit condition vulnerability in Junrar from Junrar Project, 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 version 7.4.1 as the first without the flaw, so updating Junrar to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 1.63% chance of exploitation within 30 days, higher than 77% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Junrar to 7.4.1 or a later version.
  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
Junrar ProjectJunrarbefore 7.4.17.4.1

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
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 2.05.0MediumNVD

Official description

Junrar is an open source java RAR archive library. In affected versions A carefully crafted RAR archive can trigger an infinite loop while extracting said archive. The impact depends solely on how the application uses the library, and whether files can be provided by malignant users. The problem is patched in 7.4.1. There are no known workarounds and users are advised to upgrade as soon as possible.

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

The underlying weakness: Loop with Unreachable Exit Condition

The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop.

More Loop with Unreachable Exit Condition vulnerabilities (CWE-835)

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)

Recent Loop with Unreachable Exit Condition vulnerabilities

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