Description
wp-admin/user-new.php in WordPress before 4.9.1 sets the newbloguser key to a string that can be directly derived from the user ID, which allows remote attackers to bypass intended access restrictions by entering this string.
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 | wordpress | 4.9.1+dfsg-1 | — |
| Debian 13 | wordpress | 4.9.1+dfsg-1 | — |
| Debian 12 | wordpress | 4.9.1+dfsg-1 | — |
| Debian 9 | wordpress | 4.7.5+dfsg-2+deb9u2 | DSA-4090-1 |
| Debian 8 | wordpress | 4.1+dfsg-1+deb8u16 | DSA-4090-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 7 | wordpress | 3.6.1+dfsg-1~deb7u20 | DLA-1216-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | wordpress | No fix yet | — |
Advisories 2
- DSA-4090-1 wordpress - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-1216-1 wordpress - security update Debian Security (DSA / DLA) · Mar 9, 2026
References
- DSA-4090 vendor-advisory
- https://wpvulndb.com/vulnerabilities/8969
- [debian-lts-announce] 20171221 [SECURITY] [DLA 1216-1] wordpress security update mailing-list
- 102024 vdb-entry
- https://codex.wordpress.org/Version_4.9.1
- https://github.com/WordPress/WordPress/commit/eaf1cfdc1fe0bdffabd8d879c591b864d833326c
- https://wordpress.org/news/2017/11/wordpress-4-9-1-security-and-maintenance-release/