CVE-2026-23739

Asterisk xml.c uses unsafe XML_PARSE_NOENT leading to potential XXE Injection

MEDIUM
6.5
CVSS Score
Published: February 6, 2026 at 04:42 PM UTC
Updated: June 17, 2026 at 10:22 AM UTC
3 products affected across 2 vendorsAsteriskCertified AsteriskAsterisk

Using asterisk by asterisk?

Get instant alerts when new vulnerabilities affect asterisk - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
MEDIUM6.5
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

Description

Asterisk is an open source private branch exchange and telephony toolkit. Prior to versions 20.7-cert9, 20.18.2, 21.12.1, 22.8.2, and 23.2.2, the ast_xml_open() function in xml.c parses XML documents using libxml with unsafe parsing options that enable entity expansion and XInclude processing. Specifically, it invokes xmlReadFile() with the XML_PARSE_NOENT flag and later processes XIncludes via xmlXIncludeProcess().If any untrusted or user-supplied XML file is passed to this function, it can allow an attacker to trigger XML External Entity (XXE) or XInclude-based local file disclosure, potentially exposing sensitive files from the host system. This can also be triggered in other cases in which the user is able to supply input in xml format that triggers the asterisk process to parse it. This issue has been patched in versions 20.7-cert9, 20.18.2, 21.12.1, 22.8.2, and 23.2.2.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 20.18.221.0.0 ≤ v < 21.12.122.0.0 ≤ v < 22.8.223.0.0 ≤ v < 23.2.2
v < 20.18.2v < 20.7-cert9v < 21.12.1v < 22.8.2v < 23.2.2
Affected range stops below 20.18.2, so it looks safe — our inference, not a vendor statement
Affected range stops below 20.7-cert9, so it looks safe — our inference, not a vendor statement
Affected range stops below 21.12.1, so it looks safe — our inference, not a vendor statement
Affected range stops below 22.8.2, so it looks safe — our inference, not a vendor statement
Affected range stops below 23.2.2, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (1)

x_refsource_CONFIRMVendor Advisory
Source: cverecord
https://github.com/asterisk/asterisk/security/advisories/GHSA-85x7-54wr-vh42

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-611

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card