CyberSecBulletin
CVE-2022-47516NVD status: Modified

Drachtio-server: Reachable Assertion

CVE-2022-47516 is a high-severity reachable assertion vulnerability in Drachtio-server from Drachtio, 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 0.8.20 as the first without the flaw, so updating Drachtio-server to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 1.76% chance of exploitation within 30 days, higher than 78% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Drachtio-server to 0.8.20 or a later version.
  2. 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
DrachtioDrachtio-serverbefore 0.8.200.8.20

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 3.17.5HighCISA (ADP)

Official description

An issue was discovered in the libsofia-sip fork in drachtio-server before 0.8.20. It allows remote attackers to cause a denial of service (daemon crash) via a crafted UDP message that leads to a failure of the libsofia-sip-ua/tport/tport.c self assertion.

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

The underlying weakness: Reachable Assertion

The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.

How developers prevent this class of flaw

  • If the assertion statement is required (e.g., for security or reliability), change the invoking code to avoid the conditions that trigger the assertion.
  • Consider changing the assertion to some other less fatal error. This might not be easy to implement, since other code may be needed to handle the error.
  • Make sensitive open/close operations non-reachable from directly user-controlled data (e.g. open/close resources)

More Reachable Assertion vulnerabilities (CWE-617)

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)

Other vulnerabilities in Drachtio-server

All Drachtio-server vulnerabilities

Recent Reachable Assertion vulnerabilities

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