CVE-2026-47783 Information disclosure in memcached
An attacker can exploit a timing side channel in memcached SASL authentication to enumerate valid usernames when password database authentication is enabled.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-47783?
CVE-2026-47783 is a high-severity vulnerability in memcached, published on 20 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In memcached before 1.6.42, username data for SASL password database authentication has a timing side channel because a loop exits as soon as a valid username is found by sasl_server_userdb_checkpass.
Weakness: CWE-208
Which versions are affected by CVE-2026-47783?
1 open source package ship an affected version, including memcached. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
memcached Bitnami | All versions | 1.6.42 |
Linux distribution packages (14)
memcached AlmaLinux:10 | All versions | 1.6.23-7.el10_2.1 |
memcached-selinux AlmaLinux:10 | All versions | 1.6.23-7.el10_2.1 |
memcached AlmaLinux:9 | All versions | 1.6.9-7.el9_8.1 |
memcached-selinux AlmaLinux:9 | All versions | 1.6.9-7.el9_8.1 |
memcached Red Hat:enterprise_linux:10.2 | All versions | 0:1.6.23-7.el10_2.1 |
memcached-debuginfo Red Hat:enterprise_linux:10.2 | All versions | 0:1.6.23-7.el10_2.1 |
memcached-debugsource Red Hat:enterprise_linux:10.2 | All versions | 0:1.6.23-7.el10_2.1 |
memcached-selinux Red Hat:enterprise_linux:10.2 | All versions | 0:1.6.23-7.el10_2.1 |
memcached Red Hat:enterprise_linux:9::appstream | All versions | 0:1.6.9-7.el9_8.1 |
memcached-debuginfo Red Hat:enterprise_linux:9::appstream | All versions | 0:1.6.9-7.el9_8.1 |
memcached-debugsource Red Hat:enterprise_linux:9::appstream | All versions | 0:1.6.9-7.el9_8.1 |
memcached-selinux Red Hat:enterprise_linux:9::appstream | All versions | 0:1.6.9-7.el9_8.1 |
memcached Rocky Linux:10 | All versions | 0:1.6.23-7.el10_2.1 |
memcached Rocky Linux:9 | All versions | 0:1.6.9-7.el9_8.1 |
Products include Memcached Memcached.
How do I fix CVE-2026-47783?
Upgrade memcached to 1.6.42 or later.
Is CVE-2026-47783 being exploited?
There is no known exploitation of CVE-2026-47783 in the wild and no public exploit code.
Other vulnerabilities in memcached
Sources
Also known as ALSA-2026:27842, ALSA-2026:27862, AZL-87008, BIT-memcached-2026-47783, CLSA-2026-1783629498, CLSA-2026-1783635895 and 9 more.