No exploitation reportedFix available

CVE-2026-47783

Q: Is CVE-2026-47783 actively exploited?

Active exploitation of CVE-2026-47783 has not been confirmed. Its EPSS score was 1.3% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

Q: What is the CVSS score for CVE-2026-47783?

CVE-2026-47783 has a CVSS v3 base score of 8.1 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.

No exploitation reported by the sources we read.

Published2026-05-20
Fixed in1.6.42
WeaknessCWE-208

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

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.

Timeline

dates in UTC

2026-05-2007:16CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-47783?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-47783?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD · OSV

Memcached

Branch	Affected	Fixed in	Source
1.6	< 1.6.42	1.6.42	NVD · OSV

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

memcachedAlmaLinux:10all versions · fixed in 1.6.23-7.el10_2.1and 1 other package
memcachedAlmaLinux:9all versions · fixed in 1.6.9-7.el9_8.1and 1 other package

Vendor advisories

CVE-2026-47783 Red Hat Product Security41 products fixed
memcached: memcached: Username enumeration via timing side channel
RHSA-2026:63224 Red Hat Product Security7 products fixed
Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update
RHSA-2026:27862 Red Hat Product Security17 products fixed
Red Hat Security Advisory: memcached security update
RHSA-2026:27842 Red Hat Product Security17 products fixed
Red Hat Security Advisory: memcached security update

Full record on NVD

Fix

Update Memcached to 1.6.42
Vendor fix Red Hat Product Security RHSA-2026:63224 · 7 productsFor details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/
Vendor fix Red Hat Product Security RHSA-2026:27862 · 17 productsFor details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258

Advisories and patches

github.comPatch
github.comRelease Notes
github.comRelease Notes

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

NVDCVE recordread 2026-10-23
CISA-ADPSSVC decisionnone2026-05-20
OpenCVESSVC decisionnone—
CNACVSS 3.18.1read 2026-10-23
CNAweakness (CWE)CWE-208read 2026-10-23
FIRST EPSSEPSS score1.3 %2026-10-23
OSVaffected packages—
Microsoft MSRCadvisory—

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Published: 2026-05-20
Last Modified: 2026-09-18
NVD status: Modified
MSRC Title: 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.

Frequently asked questions

What is CVE-2026-47783?

Is CVE-2026-47783 actively exploited?

Active exploitation of CVE-2026-47783 has not been confirmed. Its EPSS score was 1.3% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-47783?

CVE-2026-47783 has a CVSS v3 base score of 8.1 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.

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