| Name | CVE-2019-18886 |
| Description | An issue was discovered in Symfony 4.2.0 to 4.2.11 and 4.3.0 to 4.3.7. The ability to enumerate users was possible due to different handling depending on whether the user existed when making unauthorized attempts to use the switch users functionality. This is related to symfony/security. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| References | DLA-1999-1 |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|
| symfony (PTS) | jessie, jessie (lts) | 2.3.21+dfsg-4+deb8u6 | fixed |
| stretch (security) | 2.8.7+dfsg-1.3+deb9u3 | fixed |
| stretch (lts), stretch | 2.8.7+dfsg-1.3+deb9u5 | fixed |
| buster (security), buster, buster (lts) | 3.4.22+dfsg-2+deb10u3 | fixed |
| bullseye | 4.4.19+dfsg-2+deb11u6 | fixed |
| bookworm | 5.4.23+dfsg-1+deb12u2 | fixed |
| bookworm (security) | 5.4.23+dfsg-1+deb12u4 | fixed |
| sid, trixie | 6.4.15+dfsg-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|
| symfony | source | wheezy | (unfixed) | end-of-life | | |
| symfony | source | jessie | 2.3.21+dfsg-4+deb8u6 | | DLA-1999-1 | |
| symfony | source | stretch | (not affected) | | | |
| symfony | source | buster | (not affected) | | | |
| symfony | source | (unstable) | 4.3.8+dfsg-1 | | | |
Notes
[buster] - symfony <not-affected> (Vulnerability introduced in 4.1.0)
[stretch] - symfony <not-affected> (Vulnerability introduced in 4.1.0)
https://symfony.com/blog/cve-2019-18886-prevent-user-enumeration-using-switch-user-functionality
Introduced by: https://github.com/symfony/symfony/commit/6e6ac9eaeec9e6a6cc0ab003cac3738460542b0a (v4.1.0-BETA1)
Previous versions asserts "the current user is granted to switch" BEFORE
"loading the user" and thus are not affected.
Fixed by: https://github.com/symfony/symfony/commit/7bd4a92fc9cc15d9a9fbb9eb1041e01b977f8332 (v4.2.12)