UBUNTU-CVE-2026-48859
- Source
- https://ubuntu.com/security/CVE-2026-48859
- Import Source
- https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-48859.json
- JSON Data
- https://api.osv.dev/v1/vulns/UBUNTU-CVE-2026-48859
- Upstream
- Published
- 2026-06-10T16:17:00Z
- Modified
- 2026-10-06T23:31:18Z
- Severity
-
- 6.3 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N CVSS Calculator
- 5.3 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N CVSS Calculator
- Ubuntu - medium
- Summary
- [none]
- Details
-
Observable Timing Discrepancy vulnerability in Erlang/OTP ssh (ssh_auth, ssh_options modules) allows unauthenticated remote username enumeration via timing side-channel in password authentication. When the SSH daemon is configured with the user_passwords or password option, ssh_auth:check_password/3 performs a PBKDF2-SHA256 computation with 600,000 iterations (~300ms) for valid usernames, but returns immediately (~0ms) for invalid usernames via the ssh_options:get_password_option/2 path. This timing difference is detectable in a single authentication attempt and allows an unauthenticated attacker to distinguish valid from invalid usernames. The user_passwords and password options are documented as intended for test purposes; the recommended alternative is pwdfun, which is not affected by this vulnerability. This vulnerability is associated with program files lib/ssh/src/ssh_auth.erl and lib/ssh/src/ssh_options.erl. This issue affects OTP from OTP 29.0 before OTP 29.0.2, corresponding to ssh from 6.0 before 6.0.1.
- References
Affected packages
Ubuntu:25.10 / erlang
Package
- Name
- erlang
- Purl
- pkg:deb/ubuntu/erlang?arch=source&distro=questing
Affected ranges
- Type
- ECOSYSTEM
- Events
-
Introduced0 Unknown introduced version / All previous versions are affected
Affected versions
1:27.*
Ecosystem specific
{
"binaries": [
{
"binary_name": "erlang",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-asn1",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-base",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-common-test",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-crypto",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-debugger",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-dialyzer",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-diameter",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-edoc",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-eldap",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-et",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-eunit",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-examples",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-ftp",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-inets",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-jinterface",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-megaco",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-mnesia",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-mode",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-nox",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-observer",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-odbc",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-os-mon",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-parsetools",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-public-key",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-reltool",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-runtime-tools",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-snmp",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-src",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-ssh",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-ssl",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-syntax-tools",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-tftp",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-tools",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-wx",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-x11",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
},
{
"binary_name": "erlang-xmerl",
"binary_version": "1:27.3.4.1+dfsg-1ubuntu0.1"
}
]
}