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Fencer Vulns
high 8.1

CVE-2026-47783 json

In memcached before 1.6.42, username data for SASL password database authentication has a timing side channel because a loop exits as soon…

published 2026-05-20 5 mo ago modified 2026-09-18 51 d ago also BIT-memcached-2026-47783 , EUVD-2026-31065

cvss
8.1
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
1.3%
EPSS 1.3% chance of exploitation in 30 days, percentile 69%
public exploits
0
none known

Summary

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.

Patch / fix

  • bitnami memcached 1.6.42
  • memcached memcached 1.6.42
  • Red Hat Red Hat Enterprise Linux 10 0:1.6.23-7.el10_2.1
  • Red Hat Red Hat Enterprise Linux 9 0:1.6.9-7.el9_8.1
  • memcached Debian 12 1.6.18-1+deb12u1
  • memcached Debian 14 1.6.42-1

debian advisories DEBIAN-CVE-2026-47783

  • memcached Ubuntu 22.04 LTS 1.6.14-1ubuntu0.2
  • memcached Ubuntu 24.04 LTS 1.6.24-1ubuntu0.1
  • memcached Ubuntu 25.10 1.6.38-1ubuntu0.1
  • memcached Ubuntu 26.04 LTS 1.6.40-1ubuntu0.1

ubuntu advisories UBUNTU-CVE-2026-47783

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • memcached hummingbird 1 1.6.45-1.hum1
  • memcached-selinux hummingbird 1 1.6.45-1.hum1
  • memcached RHEL 9 1.6.9-7.el9_8.1
  • memcached-selinux RHEL 9 1.6.9-7.el9_8.1
  • memcached RHEL 10.2 1.6.23-7.el10_2.1
  • memcached-selinux RHEL 10.2 1.6.23-7.el10_2.1

red hat advisories RHSA-2026:63224RHSA-2026:27862RHSA-2026:27842

  • memcached SLES for SAP applications 16.0, SLES 16.0 1.6.38-160000.3.1

suse advisories SUSE-SU-2026:22022-1

  • memcached openSUSE Tumbleweed 1.6.42-1.1

opensuse advisories openSUSE-SU-2026:10882-1

  • memcached AlmaLinux 10 1.6.23-7.el10_2.1
  • memcached-selinux AlmaLinux 10 1.6.23-7.el10_2.1
  • memcached AlmaLinux 9 1.6.9-7.el9_8.1
  • memcached-selinux AlmaLinux 9 1.6.9-7.el9_8.1

almalinux advisories ALSA-2026:27842ALSA-2026:27862

  • memcached Rocky Linux 10 1.6.23-7.el10_2.1
  • memcached Rocky Linux 9 1.6.9-7.el9_8.1

rocky linux advisories RLSA-2026:27842RLSA-2026:27862

  • memcached Azure Linux 3.0 1.6.27-5

azure linux advisories AZL-87008

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-47783 updated cvss 8.1

memcached: memcached: Username enumeration via timing side channel

  • Red Hat Enterprise Linux AppStream (v. 9) memcached 1.6.9-7.el9_8.1, memcached-selinux 1.6.9-7.el9_8.1
    fixed: vendor fix RHSA-2026:27862
  • Red Hat Enterprise Linux AppStream (v. 10) memcached 1.6.23-7.el10_2.1, memcached-selinux 1.6.23-7.el10_2.1
    fixed: vendor fix RHSA-2026:27842
  • Red Hat Hardened Images memcached 1.6.45-1.hum1, memcached-selinux 1.6.45-1.hum1
    fixed: vendor fix RHSA-2026:63224
  • Red Hat Enterprise Linux 6 memcached
    not affected: vulnerable code not present
  • Red Hat Enterprise Linux 7 memcached
    not affected: vulnerable code not in execute path
  • Red Hat Enterprise Linux 8 memcached
    not affected: component not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
5 mo ago

Exploit prediction

1.26% chance of exploitation in the next 30 days, higher than 69% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 8.1 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA ADP 3.1 8.1 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
OSV 3.1 8.1 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected packages

ecosystem package affected fixed in
bitnami memcached
<1.6.42
1.6.42

Affected products

  • memcached memcached
  • Red Hat Red Hat Enterprise Linux 10
  • Red Hat Red Hat Enterprise Linux 9
  • Red Hat Red Hat Enterprise Linux 6
  • Red Hat Red Hat Enterprise Linux 7
  • Red Hat Red Hat Enterprise Linux 8
  • Red Hat Red Hat Hardened Images

Classification

Weakness
  • CWE-208 Observable Timing Discrepancy

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.