Description
Asterisk Open Source 1.2.x before 1.2.35, 1.4.x before 1.4.26.3, 1.6.0.x before 1.6.0.17, and 1.6.1.x before 1.6.1.9; Business Edition A.x.x, B.x.x before B.2.5.12, C.2.x.x before C.2.4.5, and C.3.x.x before C.3.2.2; AsteriskNOW 1.5; and s800i 1.3.x before 1.3.0.5 generate different error messages depending on whether a SIP username is valid, which allows remote attackers to enumerate valid usernames via multiple crafted REGISTER messages with inconsistent usernames in the URI in the To header and the Digest in the Authorization header.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | asterisk | 1:1.6.2.0~rc6-1 | — |
| Debian 5.0 | asterisk | 1:1.4.21.2~dfsg-3+lenny1 | DSA-1952-1 |
Advisories 1
- DSA-1952-1 asterisk - several vulnerabilities Debian Security (DSA / DLA) · Mar 9, 2026
References
- 37265 third-party-advisory
- FEDORA-2009-11126 vendor-advisory
- 37479 third-party-advisory
- 37677 third-party-advisory
- DSA-1952 vendor-advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=523277
- https://bugzilla.redhat.com/show_bug.cgi?id=533137
- 36924 vdb-entry
- FEDORA-2009-11070 vendor-advisory
- 59697 vdb-entry
- http://downloads.asterisk.org/pub/security/AST-2009-008.html
- 1023133 vdb-entry