Description
Oracle MySQL 5.1 before 5.1.49 and 5.0 before 5.0.92 allows remote authenticated users to cause a denial of service (mysqld daemon crash) by using EXPLAIN with crafted "SELECT ... UNION ... ORDER BY (SELECT ... WHERE ...)" statements, which triggers a NULL pointer dereference in the Item_singlerow_subselect::store function.
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 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Exploit-DB 1
- MySQL 5.1.48 - 'EXPLAIN' Denial of Service EDB-34506 · dos · Aug 20, 2010 · verified
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
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
- 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
- MDVSA-2011:012 vendor-advisory
- ADV-2011-0105 vdb-entry
- MDVSA-2010:222 vendor-advisory
- RHSA-2011:0164 vendor-advisory
- ADV-2011-0170 vdb-entry
- ADV-2011-0133 vdb-entry
- http://dev.mysql.com/doc/refman/5.0/en/news-5-0-92.html
- http://dev.mysql.com/doc/refman/5.1/en/news-5-1-49.html
- DSA-2143 vendor-advisory
- mysql-itemsinglerowsubselect-dos(64684) vdb-entry
- ADV-2011-0345 vdb-entry
- 42599 vdb-entry
- MDVSA-2010:155 vendor-advisory
- http://bugs.mysql.com/bug.php?id=52711
- 42936 third-party-advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=628328
- RHSA-2010:0825 vendor-advisory
- SUSE-SR:2010:019 vendor-advisory
- [oss-security] 20100928 Re: CVE Request -- MySQL v5.1.49 -- multiple DoS flaws mailing-list