CVE Intelligence
Low Memory corruption

CVE-2026-57199 — Asterisk: Asterisk app_sms.c copies externally controlled SMS lengths into fixed in-struct buffers

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, `app_sms.c` copies externally controlled `SMS` lengths into `fixed in-struct buffers` without sufficient bounds checks, allowing an attacker to corrupt memory or crash Asterisk. The administrator must explicitly use the `SMS` dialplan application, which is useful when routing calls to or from `analog devices`, and must not have ensured that data passed to the application is valid. 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.

Published Oct 27, 2026 · Updated Oct 28, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: GitHub_M

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • No scoring signals.

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
—
No EPSS score.
Affects
Asterisk
Asterisk and 1 more
CVSS base
2.3
Low · 2 source(s)

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Asterisk Asterisk, Asterisk Certified-asterisk).
  2. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  3. Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Asterisk Asterisk version < 20.20.1version >= 21.0.0-pre1, < 21.12.3version >= 22.0.0-pre1, < 22.10.1version >= 23.0.0-pre1, < 23.4.1 Vulnerable CVE Program (cve.org) e CISA ADP
Asterisk Certified-asterisk version < 20.7-cert11version >= 22.8-cert1-pre1, < 22.8-cert3 Vulnerable CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Attack requirements
Present
Privileges required
Low
User interaction
None
Scope
X
Confidentiality (vulnerable system)
None
Integrity (vulnerable system)
None
Availability (vulnerable system)
Low
Confidentiality (subsequent)
None
Integrity (subsequent)
None
Availability (subsequent)
None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
2.3 CVSS 4.0 Low — — security-advisories@github.com via NIST National Vulnerability Database
2.3 CVSS 4.0 Low — — GitHub_M via CVE Program (cve.org) e CISA ADP
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X (score shown at the top: security-advisories@github.com)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-787 · Out-of-bounds Write

Other CVEs with this weakness →

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
  • Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
web/proxy/WAF logsnetwork IDS/IPSendpoint telemetry (EDR)crash dumps

Timeline

What happened to this CVE, newest first.

  • 2026
  • Source status changed · Received → Awaiting Analysis
    Oct 28, 2026 · NIST National Vulnerability Database
  • Affected products added · asterisk/asterisk, asterisk/certified-asterisk
    Oct 27, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 27, 2026
  • CVSS changed · 2.3
    Oct 27, 2026 · NIST National Vulnerability Database
  • Source status changed · → Received
    Oct 27, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 27, 2026 · Alertas do Telegram
  • CVE published
    Oct 27, 2026 · GitHub_M

Source activity

Repeated readings are counted rather than listed.

  • 1× References added · Oct 27, 2026 – Oct 27, 2026
  • 1× Official description updated · Oct 27, 2026 – Oct 27, 2026

References

15 on the record

Elsewhere on this site

Asterisk
every CVE for this vendor
Memory corruption
same class
CWE-787
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-57192 Asterisk: Out-of-Bounds Write in Codec2 Decoder Due to Floor/Ceil Sample Count Mismatch 18h
  • CVE-2026-57190 Asterisk: SQL Injection in cel_pgsql and cel_tds via CELGenUserEvent eventtype Field 18h
  • CVE-2026-57191 Asterisk: Stack buffer overflow in MWI NOTIFY Message-Account parsing 18h
  • CVE-2026-57203 Asterisk: Local privilege escalation through ast_loggrabber's world-writable helper location 18h
  • CVE-2026-57186 Asterisk: CVE-2022-37325 fix is absent from current chan_ooh323 Q.931 party-number parser 18h
  • CVE-2026-57195 Asterisk: NULL Pointer Dereference in HTTP AMI Digest Authentication 19h

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No FIRST EPSS score.
  • No fixed version, patch or mitigation documented.
  • No CISA SSVC assessment.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-57199 is "Asterisk: Asterisk app_sms.c copies externally controlled SMS lengths into fixed in-struct buffers", rated Low. It affects Asterisk (Asterisk); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 2.3 describes technical severity. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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