CVE-2026-9749 (GCVE-0-2026-9749)

Vulnerability from cvelistv5 – Published: 2026-06-09 22:10 – Updated: 2026-06-10 13:32
VLAI
Title
Using MaxKey() may crash the server
Summary
This issue can occur when running an aggregation pipeline that uses the internal $exchange stage configured with key-range partitioning and order-preserving delivery. If a single key range produces enough documents to fill its exchange buffer (that is, many results are routed to the same consumer), the server reaches the code path where a full per-consumer buffer is detected but the internal "high watermark" for that key range is not updated as intended.
Severity
7.1 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-10 13:32 UTC
CWE
Assigner
mongodb CNA under the mitre root
CNA scorecard C 70/100 over 235 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
MongoDB MongoDB Server Affected: 8.3.0 , < 8.3.3 (semver)
Affected: 8.2.0 , < 8.2.10 (semver)
Affected: 8.0.0 , < 8.0.24 (semver)
Affected: 7.0.0 , < 7.0.35 (semver)
guessed Create a notification for this product.
Show details on NVD website
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