CVE-2026-12958

Arbitrary file write via unchecked workspace symlink

Published Jun 23, 2026 · Updated Jun 23, 2026

Symlink following in Amazon Web Services Language Servers for AWS before 1.69.0 allows local users to write files outside a trusted workspace. When the agent writes to an in-workspace path, it follows a crafted symlink whose target lies outside the workspace boundary and modifies that external file without prompting. Exploitation requires a user to open and trust the malicious workspace, after which an agent write to the linked path triggers the unauthorized modification.

CVSS severity8.5
High
EPSS probability0.19%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Symlink following in Amazon Web Services Language Servers for AWS before 1.69.0 allows local users to write files outside a trusted workspace. When the agent writes to an in-workspace path, it follows a crafted symlink whose target lies outside the workspace boundary and modifies that external file without prompting. Exploitation requires a user to open and trust the malicious workspace, after which an agent write to the linked path triggers the unauthorized modification.

The record

CVE
CVE-2026-12958
Published
Jun 23, 2026
Updated
Jun 23, 2026
Vendor
Amazon Web Services
Product
Language Servers for AWS
Classifications
CWE-61, CAPEC-23, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 23, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 23, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <1.69.0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Amazon Web Services · Language Servers for AWSversion=0 <1.69.0

Published CVSS scores

7.8Amazon Web ServicesCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
8.5Amazon Web ServicesCVSS: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 describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-61UNIX Symbolic Link (Symlink) Following
CAPEC-23File Content Injection
T1204.002Malicious File

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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