CVE-2026-12143 (HIGH): detected in Lambda Docker Images.

[the-lambda-watchdog]

CVE Details

CVE ID	Severity	Affected Package	Installed Version	Fixed Version	Date Published	Date of Scan
CVE-2026-12143	HIGH	form-data	4.0.5	2.5.6, 3.0.5, 4.0.6	2026-06-12T19:16:26.56Z	2026-06-16T10:19:08.088601836Z

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Affected Docker Images

Image Name	SHA
public.ecr.aws/lambda/nodejs:latest	public.ecr.aws/lambda/nodejs@sha256:d01267c60e0434e803c8f0b2262f77dcfb612bbe32f7dd68ab9ac938504819b0
public.ecr.aws/lambda/nodejs:24	public.ecr.aws/lambda/nodejs@sha256:76dd5356e7fb20ca4c57b5ae30d5e80192e6822929b3c467d0614172bce3c960
public.ecr.aws/lambda/nodejs:22	public.ecr.aws/lambda/nodejs@sha256:d01267c60e0434e803c8f0b2262f77dcfb612bbe32f7dd68ab9ac938504819b0

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Description

form-data is a library for creating readable multipart/form-data streams. In versions through 4.0.5, the field argument to FormData#append and the filename option are concatenated verbatim into the Content-Disposition header without escaping carriage return (CR), line feed (LF), or double-quote (") characters. An application that passes attacker-controlled data as a field name or filename (for example, an API gateway that turns JSON object keys into multipart field names) allows the attacker to terminate the header line and inject additional headers, or to smuggle entire additional multipart parts, into the request the application forwards to a backend. This can let the attacker add or override form fields (e.g. set is_admin=true) seen by the downstream parser. This is an instance of CWE-93 (CRLF injection). The fix escapes CR, LF, and " as %0D, %0A, and %22 in field names and filenames, matching the serialization browsers use per the WHATWG HTML multipart/form-data encoding algorithm. Exploitation requires the consuming application to use untrusted input as a field name or filename; applications that use only fixed/trusted field names are not affected. Fixed in 2.5.6, 3.0.5, and 4.0.6.

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Remediation Steps

• Update the affected package form-data from version 4.0.5 to 2.5.6, 3.0.5, 4.0.6.

About this issue

• This issue may not contain all the information about the CVE nor the images it affects.
• This issue will not be updated with new information and the list of affected images may have changed since the creation of this issue.
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• This issue was created automatically by Lambda Watchdog.