CyberSecBulletin
CVE-2024-39549NVD status: Modified

Junos OS: Missing Release of Memory after Effective Lifetime

CVE-2024-39549 is a high-severity missing release of memory after effective lifetime vulnerability in Junos OS from Juniper Networks, 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 versions 21.2R3-S8, 21.4R3-S8, 22.2R3-S4 as the first without the flaw, so updating Junos OS to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.47% 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. Update Junos OS to 21.2R3-S8 or 21.4R3-S8 or 22.2R3-S4 or 22.3R3-S3, whichever matches your release line, or a later version.
  2. Update Junos OS Evolved to 21.2R3-S8-EVO or 21.4R3-S8-EVO or 22.2R3-S4-EVO or 22.3R3-S3-EVO, whichever matches your release line, or a later version.
  3. Read the advisory on supportportal.juniper.net for workarounds and exact fixed builds.
  4. 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
Juniper NetworksJunos OSbefore 21.2R3-S8; 21.4 up to, but not including, 21.4R3-S8; 22.2 up to, but not including, 22.2R3-S4; 22.3 up to, but not including, 22.3R3-S3; 22.4 up to, but not including, 22.4R3-S3; 23.2 up to, but not including, 23.2R2-S1; 23.4 up to, but not including, 23.4R1-S2, 23.4R2; 23.4 up to, but not including, 23.4R1-S2; and 2 more ranges21.2R3-S8, 21.4R3-S8, 22.2R3-S4, 22.3R3-S3, 22.4R3-S3, 23.2R2-S1
Juniper NetworksJunos OS Evolvedbefore 21.2R3-S8-EVO; 21.4 up to, but not including, 21.4R3-S8-EVO; 22.2 up to, but not including, 22.2R3-S4-EVO; 22.3 up to, but not including, 22.3R3-S3-EVO; 22.4 up to, but not including, 22.4R3-S3-EVO; 23.2 up to, but not including, 23.2R2-S1-EVO; 23.4 up to, but not including, 23.4R1-S2-EVO, 23.4R2-EVO; 23.4 up to, but not including, 23.4R1-S2-EVO; and 2 more ranges21.2R3-S8-EVO, 21.4R3-S8-EVO, 22.2R3-S4-EVO, 22.3R3-S3-EVO, 22.4R3-S3-EVO, 23.2R2-S1-EVO
Juniper NetworksJunos21.1 and earlier; 21.2; 21.4; 22.2; 22.3; 22.4; 23.2; 23.4; and 1 more rangesNot 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 CNA (juniper.net).

Scoring systemScoreSeverityScored by
CVSS 4.08.7HighCNA (juniper.net)
CVSS 3.17.5HighCNA (juniper.net)

Official description

A Missing Release of Memory after Effective Lifetime vulnerability in the routing process daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows an attacker to send a malformed BGP Path attribute update which allocates memory used to log the bad path attribute. This memory is not properly freed in all circumstances, leading to a Denial of Service (DoS). Consumed memory can be freed by manually restarting Routing Protocol Daemon (rpd). Memory utilization could be monitored by: user@host> show system memory or show system monitor memory status This issue affects: Junos OS: * All versions before 21.2R3-S8, * from 21.4 before 21.4R3-S8, * from 22.2 before 22.2R3-S4, * from 22.3 before 22.3R3-S3, * from 22.4 before 22.4R3-S3, * from 23.2 before 23.2R2-S1, * from 23.4 before 23.4R1-S2, 23.4R2. Junos OS Evolved: * All versions before 21.2R3-S8-EVO, * from 21.4 before 21.4R3-S8-EVO, * from 22.2 before 22.2R3-S4-EVO, * from 22.3 before 22.3R3-S3-EVO, * from 22.4 before 22.4R3-S3-EVO, * from 23.2 before 23.2R2-S1-EVO, * from 23.4 before 23.4R1-S2-EVO, 23.4R2-EVO.

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: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Junos OS

All Junos OS vulnerabilities

Recent Missing Release of Memory after Effective Lifetime vulnerabilities

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