CyberSecBulletin
CVE-2022-26498NVD status: Modified

Asterisk: Uncontrolled Resource Consumption

CVE-2022-26498 is a high-severity uncontrolled resource consumption vulnerability in Asterisk from Digium, 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 18.11.2 as the first without the flaw, so updating Asterisk to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 16.5% chance of exploitation within 30 days, which is in the top 2.95% of all scored CVEs.

Patch this week

EPSS places it among the vulnerabilities most likely to be exploited soon.

What to do

  1. Update Asterisk to 18.11.2 or a later version.
  2. Read the advisory on packetstormsecurity.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
DigiumAsterisk16.15.0 through 16.25.1; 18.0 up to, but not including, 18.11.2; 19.0.0 through 19.3.118.11.2
DebianDebian Linux10.0; 11.0Not stated

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 3.17.5HighNVD
CVSS 2.05.0MediumNVD

Official description

An issue was discovered in Asterisk through 19.x. When using STIR/SHAKEN, it is possible to download files that are not certificates. These files could be much larger than what one would expect to download, leading to Resource Exhaustion. This is fixed in 16.25.2, 18.11.2, and 19.3.2.

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

The underlying weakness: Uncontrolled Resource Consumption

The product does not properly control the allocation and maintenance of a limited resource.

How developers prevent this class of flaw

  • Ensure that protocols have specific limits of scale placed on them.
  • Ensure that all failures in resource allocation place the system into a safe posture.

More Uncontrolled Resource Consumption vulnerabilities (CWE-400)

Timeline

  1. CVE record published.
  2. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in Asterisk

All Asterisk vulnerabilities

Recent Uncontrolled Resource Consumption vulnerabilities

Spotted an error? Tell us.