CVE-2021-3757
Prototype Pollution in immerjs/immer
immer is vulnerable to Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Prototype Pollution in immerjs/immer
immer is vulnerable to Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')
- Record
CVE-2021-3757- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-1321
- Updated
- 2026-11-02
EUVDEUVD-2021-2031
immer is vulnerable to Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')
- Record
EUVD-2021-2031- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-c36v-fmgq-m8hx
Prototype Pollution in immer
immer is vulnerable to Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution').
- Record
GHSA-c36v-fmgq-m8hx- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-915, CWE-1321
- Updated
- 2026-11-02
NVD
immer is vulnerable to Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')
- Record
CVE-2021-3757- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 7.5 High
AV:N/AC:L/Au:N/C:P/I:P/A:P - Weakness
- CWE-1321
- Updated
- 2026-11-02
OSV
immer is vulnerable to Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')
- Record
CVE-2021-3757- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVGHSA-c36v-fmgq-m8hx
Prototype Pollution in immer
immer is vulnerable to Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution').
- Record
GHSA-c36v-fmgq-m8hx- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-1321, CWE-915
- Updated
- 2026-11-02
OSVCLSA-2026-1792746527 No score
TuxCare security update for immer (2 CVEs)
TuxCare rebuilt immer to address 2 CVEs. Fixed in 8.0.1-tuxcare.1.
- Record
CLSA-2026-1792746527- Updated
- 2026-11-02
OSVROOT-APP-NPM-CVE-2021-3757 No score
CVE-2021-3757 in immer - Patched by Root
Root has patched CVE-2021-3757 in the immer package for Root:npm. Multiple fixed versions available.
- Record
ROOT-APP-NPM-CVE-2021-3757- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
immernpm |
7.0.0 up to 9.0.6 | 9.0.6 |
immerTuxCare:npm From an advisory covering 2 CVEs |
8.0.1-tuxcare.0 up to 8.0.1-tuxcare.1, plus listed versions 8.0.1 |
8.0.1-tuxcare.1 |
immerRoot:npm |
before 8.0.1-aikido.2 | 8.0.1-aikido.2 |
@rootio/immerRoot:npm |
before 8.0.1-root.io.2 | 8.0.1-root.io.2 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-3757 is a high vulnerability (CVSS 7.5) in Immer Project Immer, published September 2, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.66%, the 76th percentile. Fixed in immer 9.0.6.