CVE-2026-12958
Arbitrary file write in Language Servers for AWS
Missing symlink validation in Language Servers for AWS may allow an arbitrary file write outside of the workspace trust boundary. This may occur when a local user opens a workspace with a maliciously crafted symlink that resolves to a file path outside the workspace trust boundary.
To remediate this issue, users should upgrade to version 1.69.0 or higher.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Passive
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Arbitrary file write in Language Servers for AWS
Missing symlink validation in Language Servers for AWS may allow an arbitrary file write outside of the workspace trust boundary. This may occur when a local user opens a workspace with a maliciously crafted symlink that resolves to a file path outside the workspace trust boundary.
To remediate this issue, users should upgrade to version 1.69.0 or higher.
- Record
CVE-2026-12958- CVSS 4.0
- 8.5 High
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-61
- Updated
- 2026-11-02
EUVDEUVD-2026-38489
Missing symlink validation in Language Servers for AWS may allow an arbitrary file write outside of the workspace trust boundary. This may occur when a local user opens a workspace with a maliciously crafted symlink that resolves to a file path outside the workspace trust boundary.
To remediate this issue, users should upgrade to version 1.69.0 or higher.
- Record
EUVD-2026-38489- CVSS 4.0
- 8.5 High
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-6v3r-4p5c-mrp5
Language Servers for AWS vulnerable to arbitrary file write
Summary
Language Servers for AWS (the aws/language-servers project) provides the Language Server Protocol implementations that power AWS developer tooling, including the Amazon Q Developer agentic chat experience, across IDEs such as VS Code, JetBrains, Visual Studio, and Eclipse.
Missing symlink validation in Language Servers for AWS may allow an arbitrary file write outside of the workspace trust boundary. This may occur when a local user opens a workspace containing a maliciously crafted symlink that resolves to a file path outside the workspace trust boundary.
Impact
If a user opens a maliciously crafted workspace containing a symlink that resides within the workspace but resolves to a location outside the workspace trust boundary, the agent may follow that symlink and write to the external location without prompting the user for approval. This can result in the modification of files outside the intended workspace boundary.
This issue is triggered when a user opens a workspace, trusts it, and the agent subsequently writes to a path within that workspace.
Impacted versions: Language Servers for AWS version <1.69.0.
Patches
This issue has been addressed in AWS Language Servers version 1.69.0. We recommend upgrading to the latest version and ensuring any forked or derivative code is patched to incorporate the new fixes.
Workarounds
No workarounds are available.
References
If you have any questions or comments about this advisory, AWS Security ask that you contact them via their vulnerability reporting page or directly via email to [email protected]. Please do not create a public GitHub issue.
Acknowledgement
AWS Security would like to thank Wiz and Maor Dokhanian for collaborating on this issue through the coordinated vulnerability disclosure process.
- Record
GHSA-6v3r-4p5c-mrp5- CVSS 4.0
- 8.5 High
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-61
- Updated
- 2026-11-02
NVD
Missing symlink validation in Language Servers for AWS may allow an arbitrary file write outside of the workspace trust boundary. This may occur when a local user opens a workspace with a maliciously crafted symlink that resolves to a file path outside the workspace trust boundary.
To remediate this issue, users should upgrade to version 1.69.0 or higher.
- Record
CVE-2026-12958- CVSS 4.0
- 8.5 High
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/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 - CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-61
- Updated
- 2026-11-02
OSV
Arbitrary file write in Language Servers for AWS
Missing symlink validation in Language Servers for AWS may allow an arbitrary file write outside of the workspace trust boundary. This may occur when a local user opens a workspace with a maliciously crafted symlink that resolves to a file path outside the workspace trust boundary.
To remediate this issue, users should upgrade to version 1.69.0 or higher.
- Record
CVE-2026-12958- CVSS 4.0
- 8.5 High
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-61
- Updated
- 2026-11-02
OSVGHSA-6v3r-4p5c-mrp5
Language Servers for AWS vulnerable to arbitrary file write
Summary
Language Servers for AWS (the aws/language-servers project) provides the Language Server Protocol implementations that power AWS developer tooling, including the Amazon Q Developer agentic chat experience, across IDEs such as VS Code, JetBrains, Visual Studio, and Eclipse.
Missing symlink validation in Language Servers for AWS may allow an arbitrary file write outside of the workspace trust boundary. This may occur when a local user opens a workspace containing a maliciously crafted symlink that resolves to a file path outside the workspace trust boundary.
Impact
If a user opens a maliciously crafted workspace containing a symlink that resides within the workspace but resolves to a location outside the workspace trust boundary, the agent may follow that symlink and write to the external location without prompting the user for approval. This can result in the modification of files outside the intended workspace boundary.
This issue is triggered when a user opens a workspace, trusts it, and the agent subsequently writes to a path within that workspace.
Impacted versions: Language Servers for AWS version <1.69.0.
Patches
This issue has been addressed in AWS Language Servers version 1.69.0. We recommend upgrading to the latest version and ensuring any forked or derivative code is patched to incorporate the new fixes.
Workarounds
No workarounds are available.
References
If you have any questions or comments about this advisory, AWS Security ask that you contact them via their vulnerability reporting page or directly via email to [email protected]. Please do not create a public GitHub issue.
Acknowledgement
AWS Security would like to thank Wiz and Maor Dokhanian for collaborating on this issue through the coordinated vulnerability disclosure process.
- Record
GHSA-6v3r-4p5c-mrp5- CVSS 4.0
- 8.5 High
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-61
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
@aws/lsp-codewhisperernpm |
before 0.0.117 | 0.0.117 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-12958 is a high vulnerability (CVSS 8.5) in Amazon Web Services Language Servers For Aws, published June 23, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.19%, the 8th percentile. Fixed in @aws/lsp-codewhisperer 0.0.117.
References
aws.amazon.com/security/security-bulletins/2026-047-aws
github.com/aws/language-servers/security/advisories/GHSA-6v3r-4p5c-mrp5
nvd.nist.gov/vuln/detail/CVE-2026-12958