Asn1 TsApplication · Jonathanwilbur

CVE-2026-27452

MEDIUM · 5.3 CVSS v3.1 Published 2026-02-21
Fix available
A fix is available. Upgrade to 11.0.6 or later.
See remediation →
62/100
Remediation priority · Elevated
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
ASN.1 TypeScript ESM library, including codecs for Basic Encoding Rules (BER) and Distinguished Encoding Rules (DER). In versions 11.0.5 and below, in some cases, decoding an INTEGER could leak the underlying ArrayBuffer. This issue is expected to be fixed in version 11.0.6.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

This is an information disclosure vulnerability in an ASN.1 TypeScript ESM library affecting versions 11.0.5 and below. When decoding INTEGER values using BER/DER codecs, the underlying ArrayBuffer can be leaked in certain cases, potentially exposing sensitive memory contents to attackers who control or influence the ASN.1 data being decoded.

MitigationUpgrade to version 11.0.6 once released. Until then, avoid processing untrusted ASN.1 INTEGER data with this library and validate all incoming ASN.1 content before decoding.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Asn1 TsApplication
Affected:< 11.0.6

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify if the Asn1 Ts library is in use
    Search your codebase for imports of 'asn1-ts' or '@asn1ts' package, or check your package-lock.json/package.json for this dependency
    Affected if The library is present in dependencies
  2. Check installed version of the library
    Run 'npm list asn1-ts' or 'npm list @asn1ts' or inspect node_modules/asn1-ts/package.json to find the version field
    Affected if Version is 11.0.5 or below (any version less than 11.0.6)
  3. Verify BER or DER codec usage for INTEGER decoding
    Search your codebase for calls to BER or DER decoder functions, particularly those processing INTEGER types, such as 'BER.decode', 'DER.decode', or similar methods from the library
    Affected if Your code uses BER or DER to decode INTEGER values from ASN.1 data
  4. Determine source of ASN.1 data being decoded
    Inspect the data source passed to the BER/DER decode functions - check if it originates from external/ network sources, user input, files from untrusted sources, or other potentially attacker-controlled inputs
    Affected if The ASN.1 data being decoded comes from untrusted or externally controlled sources

You are affected if the Asn1 Ts library version is below 11.0.6 AND your code uses BER/DER codecs to decode INTEGER values from untrusted ASN.1 data sources.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 11.0.6 or later
Fixed in 11.0.6
Interim mitigation

Upgrade to version 11.0.6 once released. Until then, avoid processing untrusted ASN.1 INTEGER data with this library and validate all incoming ASN.1 content before decoding.

Recommended fix High confidence

11.0.6

  1. Upgrade the @hnie/asn1-ts package to version 11.0.6 or later
  2. Run npm update @hnie/asn1-ts or npm install @hnie/asn1-ts@latest to apply the fix
  3. Verify the version was updated by checking package.json or running npm list @hnie/asn1-ts

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Asn1 Ts Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing4.0 h
  • Review / QA2.0 h
12.0 hours of engineering $2,080
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,328.

Scan for this in your stack

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dbcve dependency scanner

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-27452 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data