{"id":"GHSA-h6j4-qpp7-q28p","kind":"vulnerability","aliases":["GHSA-h6j4-qpp7-q28p"],"related":[],"title":"CVE-2026-107608: Improper link resolution in asset bundling output handling in aws-cdk-lib","description":"CVE-2026-107608: Improper link resolution in asset bundling output handling in aws-cdk-lib\n\n### CVE-2026-107608: Improper link resolution in asset bundling output handling in aws-cdk-lib\n\nBulletin ID: 2026-131-AWS Scope: AWS Content Type: Important (requires attention) Publication Date: 10/08/2026 12:30 PM PDT\n\nDescription:\n\nAWS CDK is an open source framework that allows customers to build cloud infrastructure using their favorite programming language (Python, Typescript, C#, Go). That infrastructure is then able to be deployed with AWS CDK command line commands to AWS CloudFormation. We identified CVE-2026-107608, which is an issue where Docker files could be configured to insert symlinked files into the output of the AWS CDK asset bundling process when it was invoked with a Docker file. When bundling an asset using AWS CDK with a docker file, prior to 2.267.0, it was possible for a docker file to insert a symlinked file or directory into the output of asset bundling without the symlink having been provided as input to the bundling process.\n\nImpacted versions: All aws-cdk-lib versions before 2.267.0\n\nResolution:\n\nThis issue has been addressed in aws-cdk-lib version 2.267.0. We recommend upgrading to the latest version and ensuring any forked or derivative code is patched to incorporate the new fixes.\n\nWorkarounds:\n\nIf you cannot immediately upgrade, you can reduce the possibility of streaming unexpected information by auditing all Docker bundling containers and their dependencies to confirm that no untrusted code executes inside the configured bundling environment.\n\nReferences:\n\n- CVE-2026-107608\n- GHSA-h6j4-qpp7-q28p\n\n Please email aws-security@amazon.com with any security questions or concerns.","summary":"When aws-cdk-lib bundles an asset with a Docker file, a malicious Docker build can insert symlinks into the bundling output that were never declared as inputs. Those links can point at files outside the bundle, so the synthesized output may carry data the project did not intend to deploy.","severity":"medium","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["aws","aws-cdk","infrastructure-as-code","lab-disclosure","package","python","typescript"],"not_affected_if":["no-docker-bundling","trusted-bundling-images"],"how_to_check":"- Run `npm ls aws-cdk-lib` (or check the lockfile) to find the installed `aws-cdk-lib` version.\n- Review Dockerfiles and bundling images used by `Code.fromAsset` or `DockerImage` bundling and confirm they come from trusted sources.","fix":"- Upgrade `aws-cdk-lib` to `2.267.0` or later.\n- Patch any forked or derivative CDK code as the bulletin recommends.\n- Until upgraded, audit Docker bundling containers and their dependencies to confirm no untrusted code runs inside them.","status":"open","published_at":null,"first_seen_at":"2026-10-24T19:28:16+00:00","triaged_at":"2026-10-25T04:50:16+00:00","updated_at":"2026-10-26T00:58:05+00:00","category":"package","confidence":0.6,"triage":{"at":"2026-10-25T04:50:16Z","model":"claude-haiku-5-5","output":{"fix":"- Upgrade `aws-cdk-lib` to `2.267.0` or later.\n- Patch any forked or derivative CDK code as the bulletin recommends.\n- Until upgraded, audit Docker bundling containers and their dependencies to confirm no untrusted code runs inside them.","reach":"local","title":"AWS CDK: symlinked Docker bundling output can expose host files","impact":"medium","summary":"When aws-cdk-lib bundles an asset with a Docker file, a malicious Docker build can insert symlinks into the bundling output that were never declared as inputs. Those links can point at files outside the bundle, so the synthesized output may carry data the project did not intend to deploy.","category":"package","nicknames":[],"who_cares":["aws-cdk","infrastructure-as-code","aws","typescript","python"],"confidence":0.6,"needs_auth":"unknown","worst_case":"Symlinks to outside files leak host data into deployed assets","analyst_note":"","how_to_check":"- Run `npm ls aws-cdk-lib` (or check the lockfile) to find the installed `aws-cdk-lib` version.\n- Review Dockerfiles and bundling images used by `Code.fromAsset` or `DockerImage` bundling and confirm they come from trusted sources.","needs_analyst":false,"not_affected_if":["no-docker-bundling","trusted-bundling-images"],"who_is_affected":"Projects that use aws-cdk-lib before 2.267.0 and bundle assets with a Dockerfile are exposed, because the bundling container can add symlinks to the output. Teams that only use non-Docker asset bundling or that never build assets in containers can skip it, as can those whose bundling images are fully trusted.","user_interaction":"no","needs_special_setup":"yes","severity_if_unknown":"medium"},"cost_usd":0.000706,"input_tokens":3891,"output_tokens":633,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-107608':3A,95C,111C,189C,351C '-131':128C '-2026':2A,94C,110C,188C,350C '10/08/2026':139C '12':140C '2.267.0':235C,277C,290C '2026':127C '30':141C 'abl':172C 'address':283C 'allow':153C 'asset':8A,48B,100C,116C,211C,225C,254C 'attent':136C 'audit':328C 'aw':14A,27B,29B,43B,106C,122C,129C,131C,145C,177C,183C,209C,227C,272C,286C 'aws-cdk':28B 'aws-cdk-lib':13A,42B,105C,121C,271C,285C 'aws-security@amazon.com':359C 'build':56B,156C 'bulletin':125C 'bundl':9A,46B,62B,78B,101C,117C,212C,223C,255C,266C,331C,346C 'c':166C 'cannot':315C 'carri':84B 'cdk':15A,30B,44B,107C,123C,146C,178C,210C,228C,273C,287C 'cloud':157C 'cloudform':184C 'code':34B,304C,341C 'command':179C,181C 'concern':365C 'configur':199C,345C 'confirm':337C 'contain':332C 'content':132C 'could':197C 'custom':154C 'cve':1A,93C,109C,187C,349C 'data':85B 'date':138C 'declar':67B 'depend':335C 'deploy':92B,175C 'deriv':303C 'descript':144C 'directori':249C 'disclosur':37B 'docker':51B,55B,195C,220C,231C,241C,330C 'email':358C 'ensur':299C 'environ':347C 'execut':342C 'favorit':161C 'file':52B,75B,196C,203C,221C,232C,242C,247C 'fix':311C 'fork':301C 'framework':151C 'ghsa':18A,23A,353C 'ghsa-h6j4-qpp7-q28p':17A,22A,352C 'go':167C 'h6j4':19A,24A,354C 'handl':11A,103C,119C 'id':126C 'identifi':186C 'immedi':316C 'impact':268C 'import':134C 'improp':4A,96C,112C 'incorpor':308C 'inform':326C 'infrastructur':32B,158C,169C 'infrastructure-as-cod':31B 'input':69B,263C 'insert':58B,201C,244C 'insid':343C 'intend':90B 'invok':217C 'issu':193C,280C 'lab':36B 'lab-disclosur':35B 'languag':163C 'latest':296C 'lib':16A,45B,108C,124C,274C,288C 'line':180C 'link':5A,71B,97C,113C 'malici':54B 'may':83B 'never':66B 'new':310C 'open':149C 'output':10A,63B,82B,102C,118C,206C,252C 'outsid':76B 'packag':38B 'patch':306C 'pdt':143C 'pleas':357C 'pm':142C 'point':73B 'possibl':238C,322C 'prior':233C 'process':213C,267C 'program':162C 'project':87B 'provid':261C 'public':137C 'python':39B,164C 'q28p':21A,26A,356C 'qpp7':20A,25A,355C 'question':363C 'recommend':292C 'reduc':320C 'refer':348C 'requir':135C 'resolut':6A,98C,114C,278C 'scope':130C 'secur':362C 'sourc':150C 'stream':324C 'symlink':59B,202C,246C,258C 'synthes':81B 'type':133C 'typescript':40B,165C 'unexpect':325C 'untrust':340C 'upgrad':293C,317C 'use':159C,226C 'version':269C,275C,289C,297C 'without':256C 'workaround':312C","nicknames":[],"mitigations":[{"kind":"workaround","scope":"aws-cdk-lib asset bundling with Docker","since":null,"covers":"Docker-based asset bundling in aws-cdk-lib before 2.267.0, by confirming that no untrusted code executes inside the bundling containers","limits":"Does not fix the symlink insertion itself; the document states it only reduces the possibility of unexpected information being exposed","source":"https://aws.amazon.com/security/security-bulletins/rss/2026-131-aws/","vendor":"Team","seen_at":"2026-10-25T10:14:43Z","sources":["https://aws.amazon.com/security/security-bulletins/rss/2026-131-aws/"],"confidence":0.7,"source_title":"CVE-2026-107608: Improper link resolution in asset bundling output handling in aws-cdk-lib","customer_action":"Audit all Docker bundling containers and their dependencies to confirm no untrusted code executes in the bundling environment, and upgrade to aws-cdk-lib 2.267.0"},{"kind":"workaround","scope":"aws-cdk-lib Docker asset bundling","since":null,"covers":"Reduces the chance of unexpected information being exposed through Docker bundling containers by auditing them and their dependencies.","limits":"none stated","source":"https://aws.amazon.com/security/security-bulletins/rss/2026-131-aws/","vendor":"Team","seen_at":"2026-10-26T00:58:05Z","confidence":0.5,"source_title":"CVE-2026-107608: Improper link resolution in asset bundling output handling in aws-cdk-lib","customer_action":"Audit all Docker bundling containers and their dependencies to confirm that no untrusted code executes inside the configured bundling environment, until aws-cdk-lib 2.267.0 can be installed."}],"who_affected":"Projects that use aws-cdk-lib before 2.267.0 and bundle assets with a Dockerfile are exposed, because the bundling container can add symlinks to the output. Teams that only use non-Docker asset bundling or that never build assets in containers can skip it, as can those whose bundling images are fully trusted.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":null,"kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"lab","external_id":"https://aws.amazon.com/security/security-bulletins/rss/2026-131-aws/#GHSA-h6j4-qpp7-q28p","url":"https://aws.amazon.com/security/security-bulletins/rss/2026-131-aws/","severity":null,"published_at":null,"modified_at":null,"first_seen_at":"2026-10-24T19:28:16+00:00","fetched_at":"2026-10-26T00:58:58+00:00","note":"AWS: CVE-2026-107608: Improper link resolution in asset bundling output handling in aws-cdk-lib"}],"documents":[{"id":2951,"url":"https://aws.amazon.com/security/security-bulletins/rss/2026-131-aws/","title":"AWS: CVE-2026-107608: Improper link resolution in asset bundling output handling in aws-cdk-lib","kind":"advisory","source":"lab","text":"CVE-2026-107608: Improper link resolution in asset bundling output handling in aws-cdk-lib\n\n### CVE-2026-107608: Improper link resolution in asset bundling output handling in aws-cdk-lib\n\nBulletin ID: 2026-131-AWS Scope: AWS Content Type: Important (requires attention) Publication Date: 10/08/2026 12:30 PM PDT\n\nDescription:\n\nAWS CDK is an open source framework that allows customers to build cloud infrastructure using their favorite programming language (Python, Typescript, C#, Go). That infrastructure is then able to be deployed with AWS CDK command line commands to AWS CloudFormation. We identified CVE-2026-107608, which is an issue where Docker files could be configured to insert symlinked files into the output of the AWS CDK asset bundling process when it was invoked with a Docker file. When bundling an asset using AWS CDK with a docker file, prior to 2.267.0, it was possible for a docker file to insert a symlinked file or directory into the output of asset bundling without the symlink having been provided as input to the bundling process.\n\nImpacted versions: All aws-cdk-lib versions before 2.267.0\n\nResolution:\n\nThis issue has been addressed in aws-cdk-lib version 2.267.0. We recommend upgrading to the latest version and ensuring any forked or derivative code is patched to incorporate the new fixes.\n\nWorkarounds:\n\nIf you cannot immediately upgrade, you can reduce the possibility of streaming unexpected information by auditing all Docker bundling containers and their dependencies to confirm that no untrusted code executes inside the configured bundling environment.\n\nReferences:\n\n- CVE-2026-107608\n- GHSA-h6j4-qpp7-q28p\n\n Please email aws-security@amazon.com with any security questions or concerns.","published_at":null,"relation":"advisory","confidence":null,"note":null}],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}