{"affected":[{"defaultStatus":"unaffected","product":"MongoDB Server","source":"CNA: mongodb","vendor":"MongoDB","versions":[{"lessThan":"9.0.7","status":"affected","version":"9.0.0","versionType":"semver"},{"lessThan":"8.3.16","status":"affected","version":"8.3.0","versionType":"semver"}]}],"cveId":"CVE-2026-120803","cwes":["CWE-416"],"description":"A use-after-free issue exists in MongoDB’s SBE (Slot-Based Execution) implementation of a window function accumulator used by certain $setWindowFields aggregation pipelines. Under specific conditions, the accumulator can retain a dangling pointer to memory that has since been freed. When this stale pointer is later dereferenced during serialization of the carried-forward value, it can result in a heap out-of-bounds read that may expose adjacent heap contents and crash the mongod server. An authenticated user with readWrite privileges on a database can trigger this issue by crafting a specific aggregation pipeline.","epss":{"date":"2026-11-13","percentile":0.30884,"score":0.00366},"exploits":[],"kev":null,"metrics":[{"score":7.1,"severity":"high","source":"CNA: mongodb","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N","version":"4.0"},{"score":7.1,"severity":"high","source":"CNA: mongodb","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H","version":"3.1"},{"score":7.1,"severity":"high","source":"NVD: cna@mongodb.com","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","version":"4.0"},{"score":7.1,"severity":"high","source":"NVD: cna@mongodb.com","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H","version":"3.1"}],"modifiedAt":1794599282366,"publishedAt":1794340973682,"references":[{"source":"CNA: mongodb","tags":[],"url":"https://jira.mongodb.org/browse/SERVER-135180"},{"source":"cna@mongodb.com","tags":[],"url":"https://jira.mongodb.org/browse/SERVER-135180"}],"remediation":[],"revision":"6656b200258cabad4b98f1ba2f963c4383504f6b908114f96cdebdaae71fbe28","sources":[{"modifiedAt":1794599282366,"name":"CNA: mongodb","retrievedAt":1794600528243,"url":"https://www.cve.org/CVERecord?id=CVE-2026-120803"},{"modifiedAt":1794348539707,"name":"NVD","retrievedAt":1794357080360,"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-120803"},{"modifiedAt":null,"name":"FIRST EPSS","retrievedAt":1794600531588,"url":"https://api.first.org/data/v1/epss?cve=CVE-2026-120803"}],"ssvc":{"assessedAt":1794599271198,"automatable":"no","exploitation":"none","source":"ADP: CISA-ADP","technicalImpact":"partial"},"status":"published","title":"MongoDB SBE $locf Window Accumulator Use-After-Free Enables Heap OOB Read and Server Crash","updatedAt":1794600531588}