Description
MySQL 5.1 before 5.1.51 and 5.5 before 5.5.6 allows remote authenticated users to cause a denial of service (mysqld server crash) by performing a user-variable assignment in a logical expression that is calculated and stored in a temporary table for GROUP BY, then causing the expression value to be used after the table is created, which causes the expression to be re-evaluated instead of accessing its value from the table.
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 5.0 | mysql-dfsg-5.0 | 5.0.51a-24+lenny5 | DSA-2143-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 6 | mysql +7 | 5.1.52-1.el6_0.1 | RHSA-2011:0164 |
| RHEL 5 | mysql +4 | 5.0.77-4.el5_5.4 | RHSA-2010:0825 |
Advisories 3
- RHSA-2011:0164 Red Hat Security Advisory: mysql security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- RHSA-2010:0825 Red Hat Security Advisory: mysql security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- DSA-2143-1 mysql-dfsg-5.0 - several vulnerabilities Debian Security (DSA / DLA) · Mar 9, 2026
References
- http://dev.mysql.com/doc/refman/5.1/en/news-5-1-51.html
- http://dev.mysql.com/doc/refman/5.5/en/news-5-5-6.html
- USN-1397-1 vendor-advisory
- http://support.apple.com/kb/HT4723
- 42875 third-party-advisory
- USN-1017-1 vendor-advisory
- APPLE-SA-2011-06-23-1 vendor-advisory
- TLSA-2011-3 vendor-advisory
- ADV-2011-0105 vdb-entry
- MDVSA-2010:222 vendor-advisory
- RHSA-2011:0164 vendor-advisory
- ADV-2011-0170 vdb-entry
- DSA-2143 vendor-advisory
- 43676 vdb-entry
- ADV-2011-0345 vdb-entry
- mysql-uservariable-dos(64843) vdb-entry
- 42936 third-party-advisory
- RHSA-2010:0825 vendor-advisory
- http://bugs.mysql.com/bug.php?id=55564
- https://bugzilla.redhat.com/show_bug.cgi?id=640819
- MDVSA-2010:223 vendor-advisory