CVE-2021-41158Public exploitNetwork attack vector

Gateway credential disclosure via unverified SIP challenges

Published Oct 26, 2021 · Updated Aug 4, 2024

Credential disclosure in SignalWire FreeSWITCH before 1.10.7 allows remote attackers to obtain SIP gateway digest responses. sofia_reg_handle_sip_r_challenge() accepts a challenge realm from any UAC without verifying that it originated from the configured gateway. Exploitation requires causing the server to send a SIP request to the malicious party and knowing the gateway realm; the exposed response enables offline password cracking.

CVSS severity5.8
Medium
EPSS probability0.83%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Credential disclosure in SignalWire FreeSWITCH before 1.10.7 allows remote attackers to obtain SIP gateway digest responses. sofia_reg_handle_sip_r_challenge() accepts a challenge realm from any UAC without verifying that it originated from the configured gateway. Exploitation requires causing the server to send a SIP request to the malicious party and knowing the gateway realm; the exposed response enables offline password cracking.

The record

CVE
CVE-2021-41158
Published
Oct 26, 2021
Updated
Aug 4, 2024
Vendor
SignalWire
Product
FreeSWITCH
Classifications
T1110.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 26, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 1.10.7

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

SignalWire · FreeSWITCHversion=< 1.10.7

Published CVSS scores

5.8GitHub Security AdvisoryCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

T1110.002Password Cracking

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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