CVE Intelligence
Medium

CVE-2026-57193 — Asterisk: LDAP Filter Injection in res_config_ldap via SIP Username (Unauthenticated Information Disclosure)

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, the LDAP realtime driver `res_config_ldap` may permit `LDAP filter injection` through a `SIP username`, allowing an unauthenticated attacker to make arbitrary LDAP queries using carefully crafted SIP packets and disclose information. The `res_config_ldap` module must be loaded and configured to access an LDAP server, which is not the default. 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 26, 2026 · Updated Oct 26, 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
  • Technical severity (medium)+3

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
6.9
Medium · 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. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  3. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  4. Search available logs for exploit probes, 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
None
Privileges required
None
User interaction
None
Scope
X
Confidentiality (vulnerable system)
Low
Integrity (vulnerable system)
None
Availability (vulnerable system)
None
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
6.9 CVSS 4.0 Medium — — security-advisories@github.com via NIST National Vulnerability Database
6.9 CVSS 4.0 Medium — — GitHub_M via CVE Program (cve.org) e CISA ADP
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/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-943

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).
web/proxy/WAF logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · asterisk/asterisk, asterisk/certified-asterisk
    Oct 26, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 26, 2026
  • CVSS changed · 6.9
    Oct 26, 2026 · NIST National Vulnerability Database
  • Source status changed · → Received
    Oct 26, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 26, 2026 · Alertas do Telegram
  • CVE published
    Oct 26, 2026 · GitHub_M

Source activity

Repeated readings are counted rather than listed.

  • 1× References added · Oct 26, 2026 – Oct 26, 2026
  • 1× Official description updated · Oct 26, 2026 – Oct 26, 2026

References

15 on the record

Elsewhere on this site

Asterisk
every CVE for this vendor
CWE-943
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-57196 Asterisk: Reflected XSS in Phone Provisioning HTTP Error Pages 6h
  • CVE-2026-57184 Asterisk: Out-of-Bounds Read in Q.931 Information Element Parser (H.323 Addon) 6h
  • CVE-2026-57187 Asterisk: Heap-use-after-free in Asterisk PJSIP TCP/SDP handling when TCP connection closes during SDP processing 6h
  • CVE-2026-23738 The Asterisk embedded web server 's /httpstatus page echos user supplied values(cookie and query string) without sanitization Feb 6, 2026
  • CVE-2026-23740 Asterisk vulnerable to potential privilege escalation Feb 6, 2026
  • CVE-2026-23739 Asterisk xml.c uses unsafe XML_PARSE_NOENT leading to potential XXE Injection Feb 6, 2026

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-2026-57193 is "Asterisk: LDAP Filter Injection in res_config_ldap via SIP Username (Unauthenticated Information Disclosure)", rated Medium. It affects Asterisk (Asterisk); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 6.9 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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