Is CVE-2026-47783 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-47783 being exploited in the wild.

How severe is CVE-2026-47783?

High severity, with a CVSS score of 8.1, published 20 May 2026.

Is there a fix for CVE-2026-47783?

A patch was published on 2026-05-18: Fixed in memcached version 1.6.42 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-47783 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-47783?

Check whether you run Memcached at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-47783: Memcached timing side channel in SASL authentication

CVE-2026-47783 · Severity: high · CVSS 8.1 · Published 2026-05-20

Memcached is a high-performance memory caching system used to speed up web applications by storing data in RAM. A security flaw in its authentication process allows an attacker to distinguish between valid and invalid usernames by measuring how long the server takes to respond. This could allow an unauthorized user to guess valid account names or passwords, potentially leading to unauthorized access to cached data or administrative functions.

Technologies: Memcached. Vendors: Memcached.

Quick answers

Is CVE-2026-47783 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-47783 being exploited in the wild.
How severe is CVE-2026-47783?: High severity, with a CVSS score of 8.1, published 20 May 2026.
Which products and versions are affected?: Memcached before 1.6.42.
Is there a fix for CVE-2026-47783?: A patch was published on 2026-05-18: Fixed in memcached version 1.6.42 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-47783 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-47783?: Check whether you run Memcached at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A timing side-channel vulnerability exists in the sasl_server_userdb_checkpass function of memcached. The implementation used an early-exit loop when a valid username was found and utilized the non-constant-time memcmp() function for password verification. These behaviors create measurable timing discrepancies that allow a remote, unauthenticated attacker to perform username enumeration and potentially recover password bytes through timing analysis. The issue was addressed in version 1.6.42 by replacing memcmp() with a constant-time safe_memcmp() and ensuring the entire password file is scanned regardless of whether a match is found.

Affected products

memcached memcached before 1.6.42

Timeline

2026-05-18: patched: Fixed in memcached version 1.6.42
2026-05-20: disclosed: CVE-2026-47783 published

References

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