CyberSecBulletin
CVE-2024-39921NVD status: Modified

IPCOM EX2 Series: Observable Discrepancy

Published Updated By the CyberSecBulletin desk

CVE-2024-39921 is a high-severity observable discrepancy vulnerability in IPCOM EX2 Series from Fsas Technologies, 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 IPCOM EX2 Series versions: V01L02NF0001 to V01L06NF0401; V01L20NF0001 to V01L20NF0401; V02L20NF0001 to V02L21NF0301. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.43% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of IPCOM EX2 Series you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on fujitsu.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
Fsas TechnologiesIPCOM EX2 SeriesV01L02NF0001 to V01L06NF0401; V01L20NF0001 to V01L20NF0401; V02L20NF0001 to V02L21NF0301Not stated
Fsas TechnologiesIPCOM VE2 SeriesV01L04NF0001 to V01L06NF0112Not stated
FujitsuIpcom Ve2 Ls 100 Firmwarev01l04nf0001 through v01l06nf0112Not stated
FujitsuIpcom Ve2 Ls 200 Firmwarev01l04nf0001 through v01l06nf0112Not stated
FujitsuIpcom Ve2 Ls 220 Firmwarev01l04nf0001 through v01l06nf0112Not stated
FujitsuIpcom Ve2 Ls Plus 100 Firmwarev01l04nf0001 through v01l06nf0112Not stated
FujitsuIpcom Ve2 Ls Plus 200 Firmwarev01l04nf0001 through v01l06nf0112Not stated
FujitsuIpcom Ve2 Ls Plus 220 Firmwarev01l04nf0001 through v01l06nf0112Not stated
FujitsuIpcom Ve2 Ls Plus2 200 Firmwarev01l04nf0001 through v01l06nf0112Not stated
FujitsuIpcom Ve2 Ls Plus2 220 Firmwarev01l04nf0001 through v01l06nf0112Not stated
FujitsuIpcom Ve2 Sc Plus 100 Firmwarev01l04nf0001 through v01l06nf0112Not stated
FujitsuIpcom Ve2 Sc Plus 200 Firmwarev01l04nf0001 through v01l06nf0112Not stated
FujitsuIpcom Ve2 Sc Plus 220 Firmwarev01l04nf0001 through v01l06nf0112Not stated
FujitsuIpcom Ex2 In 3200 Firmwarev01l02nf0001 through v01l06nf0401; v01l20nf0001 through v01l20nf0401; v02l20nf0001 through v02l21nf0301Not stated
FujitsuIpcom Ex2 In 3500 Firmwarev01l02nf0001 through v01l06nf0401; v01l20nf0001 through v01l20nf0401; v02l20nf0001 through v02l21nf0301Not stated
FujitsuIpcom Ex2 Lb 3200 Firmwarev01l02nf0001 through v01l06nf0401; v01l20nf0001 through v01l20nf0401; v02l20nf0001 through v02l21nf0301Not stated
FujitsuIpcom Ex2 Lb 3500 Firmwarev01l02nf0001 through v01l06nf0401; v01l20nf0001 through v01l20nf0401; v02l20nf0001 through v02l21nf0301Not stated
FujitsuIpcom Ex2 Sc 3200 Firmwarev01l02nf0001 through v01l06nf0401; v01l20nf0001 through v01l20nf0401; v02l20nf0001 through v02l21nf0301Not stated
FujitsuIpcom Ex2 Sc 3500 Firmwarev01l02nf0001 through v01l06nf0401; v01l20nf0001 through v01l20nf0401; v02l20nf0001 through v02l21nf0301Not stated
FujitsuIpcom Ex2 Dc 3200 Firmwarev01l02nf0001 through v01l06nf0401; v01l20nf0001 through v01l20nf0401; v02l20nf0001 through v02l21nf0301Not stated
FujitsuIpcom Ex2 Dc 3500 Firmwarev01l02nf0001 through v01l06nf0401; v01l20nf0001 through v01l20nf0401; v02l20nf0001 through v02l21nf0301Not 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.

Scoring systemScoreSeverityScored by
CVSS 3.17.5HighNVD
CVSS 3.17.5HighCISA (ADP)

Official description

Observable timing discrepancy issue exists in IPCOM EX2 Series V01L02NF0001 to V01L06NF0401, V01L20NF0001 to V01L20NF0401, V02L20NF0001 to V02L21NF0301, and IPCOM VE2 Series V01L04NF0001 to V01L06NF0112. If this vulnerability is exploited, some of the encrypted communication may be decrypted by an attacker who can obtain the contents of the communication.

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

The underlying weakness: Observable Discrepancy

The product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor.

How developers prevent this class of flaw

  • Compartmentalize the system to have safe areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.

More Observable Discrepancy vulnerabilities (CWE-203)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Patches and release notes

Recent Observable Discrepancy vulnerabilities

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