CyberSecBulletin
CVE-2024-53980NVD status: Analyzed

RIOT: Loop with Unreachable Exit Condition

Published Updated By the CyberSecBulletin desk

CVE-2024-53980 is a high-severity loop with unreachable exit condition vulnerability in RIOT from Riot-os, 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 RIOT versions: <= 2024.07; 2024.07 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.76% chance of exploitation within 30 days, higher than 56% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of RIOT 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
RIOT-OSRIOT<= 2024.07; 2024.07 and earlierNot 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 4.06.9MediumCNA (github.com)
CVSS 3.17.5HighNVD

Official description

RIOT is an open-source microcontroller operating system, designed to match the requirements of Internet of Things (IoT) devices and other embedded devices. A malicious actor can send a IEEE 802.15.4 packet with spoofed length byte and optionally spoofed FCS, which eventually results into an endless loop on a CC2538 as receiver. Before PR #20998, the receiver would check for the location of the CRC bit using the packet length byte by considering all 8 bits, instead of discarding bit 7, which is what the radio does. This then results into reading outside of the RX FIFO. Although it prints an error when attempting to read outside of the RX FIFO, it will continue doing this. This may lead to a discrepancy in the CRC check according to the firmware and the radio. If the CPU judges the CRC as correct and the radio is set to `AUTO_ACK`, when the packet requests and acknowledgment the CPU will go into the state `CC2538_STATE_TX_ACK`. However, if the radio judged the CRC as incorrect, it will not send an acknowledgment, and thus the `TXACKDONE` event will not fire. It will then never return to the state `CC2538_STATE_READY` since the baseband processing is still disabled. Then the CPU will be in an endless loop. Since setting to idle is not forced, it won't do it if the radio's state is not `CC2538_STATE_READY`. A fix has not yet been made.

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

Patches and release notes

Other vulnerabilities in RIOT

All RIOT vulnerabilities

Recent Loop with Unreachable Exit Condition vulnerabilities

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