CVE-2026-9100: MongoDB C Driver · Improper Validation of Specified Index, Position, or Offset in Input
Affects MongoDB C DriverSource CVE Database V5
Not known to be exploited · CVSS 6.0 Medium : upgrade to 2.2.4 or 1.30.8 when convenient.
Data as of 30 Oct 2026, 06:59 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 22% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 2.2.4, 1.30.8
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 20 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Upgrade MongoDB C Driver to 2.2.4 or 1.30.8.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| MongoDB, Inc.C Driver | Affected
| Fixed in
|
| MongoDB, Inc.C Driver | Affected
| Fixed in
|
AI-suggested
If you cannot patch yet, users should consider avoiding use of the legacy GridFS API or implement additional input validation on metadata retrieved from the database to mitigate potential crashes or memory leaks.
Description
The MongoDB C Driver's legacy GridFS API accepts malformed file metadata from the database without adequate validation. Crafted documents in a GridFS collection may cause any application that reads those files via the legacy API to either crash (via a division-by-zero) or silently leak process memory contents (via an out-of-bounds read).