CVE-2026-82052: $regexFindAll may crash mongod server when byte-matching multi-byte UTF-8 chars
Vulnerability summary
CVE-2026-82052 is a high (CVSS 7.1) Reachable Assertion vulnerability in mongodb. EPSS estimates a 0.50% chance of exploitation in the next 30 days, higher than 41.7% of scored vulnerabilities.
Timeline
- 08-09-2026PublishedVulnerability first disclosed.
- 10-09-2026Last modifiedVulnerability information updated.
Description
The $regexFindAll expression can be used by an authenticated user who can run aggregation pipeline stages to crash a MongoDB server (mongod). Under certain specific conditions the regex match can start in the middle of a multi-code-unit character, triggering an assertion during query execution.
CVSS metrics
6 scores · 3 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated7.1HighCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/AU:Y/R:A
- NVDNIST7.1HighCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/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:Y/R:A/V:X/RE:X/U:X
- OSV · UbuntuEcosystem advisory · calculated6.5MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- NVDNIST6.5MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.50%
Chance of exploitation in the next 30 days
Percentile
42%
Versus all other CVEs
30-day change
Increase +0.15 pp
From 0.35% on 22-09-2026
Known exploited
Compare KEV catalogsNot in the CISA KEV catalog.
Not in the ENISA CNW catalog.
Not in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Mongodb2 products
- mongodb≥ 7.0.0, < 7.0.41 | ≥ 8.0.0, < 8.0.30 | ≥ 8.3.0, < 8.3.9
- mongodb server≥ 8.3.0, < 8.3.9 | ≥ 8.0, < 8.0.30 | ≥ 7.0, < 7.0.41
Ubuntu1 product
- mongodbAll versions (No fix recorded)
2 vendors · 3 products