CVE-2025-49832

Asterisk is Vulnerable to Remote DoS and possible RCE Attacks During Memory Allocation

MEDIUM

6.5

CVSS Score

Published: August 1, 2025 at 05:57 PM UTC

Updated: June 17, 2026 at 09:31 AM UTC

3 products affected across 2 vendorsAsteriskCertified AsteriskAsterisk

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Severity

MEDIUM6.5

Exploit prediction

EPSS 0.5%

SSVC

PoC

Description

Asterisk is an open source private branch exchange and telephony toolkit. In versions up to and including 18.26.2, between 20.00.0 and 20.15.0, 20.7-cert6, 21.00.0, 22.00.0 through 22.5.0, there is a remote DoS and possible RCE condition in `asterisk/res/res_stir_shaken /verification.c` that can be exploited when an attacker can set an arbitrary Identity header, or STIR/SHAKEN is enabled, with verification set in the SIP profile associated with the endpoint to be attacked. This is fixed in versions 18.26.3, 20.7-cert6, 20.15.1, 21.10.1 and 22.5.1.

Affected

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

Asterisk · Sangoma

95%

v < 18.26.320.0.0 ≤ v < 20.15.121.0.0 ≤ v < 21.10.122.0.0 ≤ v < 22.5.1

Affected range stops below 18.26.3, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.15.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 21.10.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 22.5.1, so it looks safe — our inference, not a vendor statement

Certified Asterisk · Sangoma

95%

v ≤ 18.920.7 cert1 20.7 cert1-rc1 20.7 cert1-rc2 20.7 cert2 20.7 cert3 20.7 cert4 20.7 cert5 20.7 cert6

Asterisk · Asterisk

60%

v < 18.26.3v < 20.15.1v < 20.7-cert7v < 21.10.1v < 22.5.1

Affected range stops below 18.26.3, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.15.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.7-cert7, so it looks safe — our inference, not a vendor statement

Affected range stops below 21.10.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 22.5.1, 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:

Patch and advisory references

https://github.com/asterisk/asterisk/security/advisories/GHSA-mrq5-74j5-f5cr

References (1)

x_refsource_CONFIRMExploitVendor Advisory

Source: [email protected]

https://github.com/asterisk/asterisk/security/advisories/GHSA-mrq5-74j5-f5cr

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

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

CVSS

6.5MEDIUMGitHub_M

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

Vector?

Quick Info

StatusANALYZED

CWE

CWE-476

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