CVE-2026-120954
Silent element-count truncation via 32-bit bit-length overflow in packed-bit vector views
A weakness in the BSON library's handling of a specialized binary vector data type allows an arithmetic wraparound when computing the number of elements described by an oversized attacker-supplied value. On builds where the platform word size is 32 bits, an application that parses untrusted BSON data can be made to process only a small fraction of the supplied elements while the operation reports success, producing results that disagree with byte-oriented accessors and with 64-bit builds of the same library. No authentication or user interaction is required beyond getting the application to parse the data. The impact is limited to data integrity; memory safety is not affected and no information is disclosed.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
6.3
Silent element-count truncation via 32-bit bit-length overflow in packed-bit vector views
A weakness in the BSON library's handling of a specialized binary vector data type allows an arithmetic wraparound when computing the number of elements described by an oversized attacker-supplied value. On builds where the platform word size is 32 bits, an application that parses untrusted BSON data can be made to process only a small fraction of the supplied elements while the operation reports success, producing results that disagree with byte-oriented accessors and with 64-bit builds of the same library. No authentication or user interaction is required beyond getting the application to parse the data. The impact is limited to data integrity; memory safety is not affected and no information is disclosed.
- Record
CVE-2026-120954- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 3.7 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-190
- Updated
- 2026-11-03
EUVDEUVD-2026-116140
6.3
A weakness in the BSON library's handling of a specialized binary vector data type allows an arithmetic wraparound when computing the number of elements described by an oversized attacker-supplied value. On builds where the platform word size is 32 bits, an application that parses untrusted BSON data can be made to process only a small fraction of the supplied elements while the operation reports success, producing results that disagree with byte-oriented accessors and with 64-bit builds of the same library. No authentication or user interaction is required beyond getting the application to parse the data. The impact is limited to data integrity; memory safety is not affected and no information is disclosed.
- Record
EUVD-2026-116140- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - Updated
- 2026-11-03
NVD
6.3
A weakness in the BSON library's handling of a specialized binary vector data type allows an arithmetic wraparound when computing the number of elements described by an oversized attacker-supplied value. On builds where the platform word size is 32 bits, an application that parses untrusted BSON data can be made to process only a small fraction of the supplied elements while the operation reports success, producing results that disagree with byte-oriented accessors and with 64-bit builds of the same library. No authentication or user interaction is required beyond getting the application to parse the data. The impact is limited to data integrity; memory safety is not affected and no information is disclosed.
- Record
CVE-2026-120954- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/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 - CVSS 3.1
- 3.7 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-190
- Updated
- 2026-11-03
OSVUBUNTU-CVE-2026-120954
6.3
A weakness in the BSON library's handling of a specialized binary vector data type allows an arithmetic wraparound when computing the number of elements described by an oversized attacker-supplied value. On builds where the platform word size is 32 bits, an application that parses untrusted BSON data can be made to process only a small fraction of the supplied elements while the operation reports success, producing results that disagree with byte-oriented accessors and with 64-bit builds of the same library. No authentication or user interaction is required beyond getting the application to parse the data. The impact is limited to data integrity; memory safety is not affected and no information is disclosed.
- Record
UBUNTU-CVE-2026-120954- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 3.7 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N - Updated
- 2026-11-05
OSVopenSUSE-SU-2026:12437-1 No score
bson-devel-2.5.8-1.1 on GA media
These are all security issues fixed in the bson-devel-2.5.8-1.1 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2026:12437-1- Updated
- 2026-11-06
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
mongo-c-driverUbuntu:Pro:20.04:LTS |
All versions, plus listed versions 1.15.0-11.15.1-11.15.2-11.16.0-11.16.1-11.16.1-1build11.16.1-1build21.16.1-1ubuntu0.1~esm1 |
None known |
mongo-c-driverUbuntu:Pro:22.04:LTS |
All versions, plus listed versions 1.18.0-11.19.1-11.19.2-11.20.0-11.20.0-1build1 Show 4 moreShow less1.20.1-11.21.0-11.21.0-1build11.21.0-1ubuntu0.1~esm1 |
None known |
mongo-c-driverUbuntu:Pro:24.04:LTS |
All versions, plus listed versions 1.24.3-11.24.4-11.25.1-11.25.2-11.25.4-1 Show 4 moreShow less1.26.0-11.26.0-1.1ubuntu11.26.0-1.1ubuntu21.26.0-1.1ubuntu2+esm1 |
None known |
mongo-c-driverUbuntu:26.10 |
All versions, plus listed versions 2.2.2-12.3.1-12.3.2-12.3.3-1build12.5.0-1 |
None known |
mongo-c-driverUbuntu:26.04:LTS |
All versions, plus listed versions 1.30.4-1ubuntu12.2.0-12.2.1-12.2.2-1 |
None known |
mongo-c-driveropenSUSE:Tumbleweed From an advisory covering 5 CVEs |
before 2.5.8-1.1 | 2.5.8-1.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, aliases, references | OSV | |
| affected, aliases, references | CVE List, EUVD, NVD, OSV | |
| aliases, products, published | EUVD | |
| first indexed | CVE List |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-120954 is a medium vulnerability (CVSS 6.3) in Mongodb C Driver, published November 3, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.23%, the 14th percentile. No source names a fixed version.