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Fencer Vulns
medium 5.9

CVE-2026-57194 json

Asterisk: chan_unistim DIALPAGE digit handling can overflow phone_number and crash Asterisk

published 2026-10-27 13 d ago modified 2026-11-02 6 d ago also EUVD-2026-111217

cvss
5.9
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 38%
public exploits
0
none known

Summary

Asterisk is an open source private branch exchange and telephony toolkit. Prior to Asterisk 20.20.1, 21.12.3, 22.10.1, 23.4.1 and Certified Asterisk 20.7-cert11, 22.8-cert3, an out-of-bounds write in `chan_unistim` `DIALPAGE` digit handling can overflow the `phone_number` field and crash Asterisk when an attacker sends a carefully crafted incoming request packet. The `chan_unistim` module must be loaded and configured with a valid `UNISTIM UDP port` that the attacker can reach. The attacker must register as a configured `phone MAC`, or the deployment must have an equivalent `production/autoprovisioning` path that allows the client to reach the main page. This issue is fixed in Asterisk 20.20.1, 21.12.3, 22.10.1, 23.4.1 and Certified Asterisk 20.7-cert11, 22.8-cert3.

Patch / fix

  • digium certified_asterisk 20.7-cert11, 20.20.1, 21.12.3, 22.8-cert3, 22.10.1, 23.4.1
  • sangoma certified_asterisk 20.7-cert11, 20.20.1, 21.12.3, 22.8-cert3, 22.10.1, 23.4.1
  • digium asterisk 20.20.1, 21.12.3, 22.10.1, 23.4.1
  • asterisk open_source 20.20.1, 21.12.3, 22.10.1, 23.4.1
  • asterisk certified_asterisk 20.7-cert11, 20.20.1, 21.12.3, 22.8-cert3, 22.10.1, 23.4.1
  • asterisk Debian 14 1:22.10.1+dfsg+~cs6.17.60671434-1

debian advisories DEBIAN-CVE-2026-57194

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-57194 updated cvss 5.9

asterisk: Asterisk: Denial of Service via out-of-bounds write in chan_unistim

  • Red Hat All currently supported Red Hat products
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
6 d ago

Exploit prediction

0.44% chance of exploitation in the next 30 days, higher than 38% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

  • asterisk asterisk
  • asterisk certified-asterisk

Classification

Weakness

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.