CVE-2025-57767 | Asterisk can crash from a specifically malformed Authorization header in an incoming SIP request

Asterisk is an open source private branch exchange and telephony toolkit. Prior to versions 20.15.2, 21.10.2, and 22.5.2, if a SIP request is received with an Authorization header that contains a realm that wasn't in a previous 401 response's WWW-Authenticate header, or an Authorization header with an incorrect realm was received without a previous 401 response being sent, the get_authorization_header() function in res_pjsip_authenticator_digest will return a NULL. This wasn't being checked before attempting to get the digest algorithm from the header which causes a SEGV. This issue has been patched in versions 20.15.2, 21.10.2, and 22.5.2. There are no workarounds.

Published: 2025-08-28 Last update: 2025-10-20 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-57767 is rated Moderate Risk (42.9/100): CVSS High severity, with low exploitation likelihood (EPSS 0.16%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-57767

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-24 0.09% 0.16% +0.08%
2 2025-08-29 — 0.09% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-57767

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2025-57767

OS Trackers for CVE-2025-57767

vendor priority summary link
alpine — CVE-2025-57767: 1 source package rows (asterisk); 101 state rows across 6 repos (3.19-main, 3.20-main, 3.21-main, 3.22-main, 3.23-main, edge-main); fixed 0, open 101. https://security.alpinelinux.org/vuln/CVE-2025-57767
debian unimportant CVE-2025-57767 unimportant priority: Debian including 1 source packages (asterisk), 2 status rows across 2 suites (bullseye, sid): resolved 2. https://security-tracker.debian.org/tracker/CVE-2025-57767
gentoo high CVE-2025-57767: 1 GLSA(s) (202601-04), 1 atom(s) (net-misc/asterisk); latest impact high. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2025-57767
ubuntu medium CVE-2025-57767 medium priority: Ubuntu including 1 source packages (asterisk), 8 status rows across 8 suites (bionic, focal, jammy, noble, plucky, questing, upstream, xenial): needs-triage 7, ignored 1. https://ubuntu.com/security/CVE-2025-57767

Affected software / configurations for CVE-2025-57767

Vendor Product Version Raw CPE
sangoma asterisk < 20.15.2 cpe:2.3:a:sangoma:asterisk:*:*:*:*:*:*:*:*
sangoma asterisk >= 21.0.0, < 21.10.2 cpe:2.3:a:sangoma:asterisk:*:*:*:*:*:*:*:*
sangoma asterisk >= 22.0.0, < 22.5.2 cpe:2.3:a:sangoma:asterisk:*:*:*:*:*:*:*:*

References for CVE-2025-57767

cvelogic Threat Intelligence