---
id: CVE-2026-54511
title: LogTape is an unobtrusive logging library
summary: >-
  LogTape is an unobtrusive logging library. Prior to 1.3.11, 2.0.14, and 2.1.5,
  the @logtape/syslog package's escapeStructuredDataValue() function in
  packages/syslog/src/syslog.ts does not neutralize C0 control characters from
  U+0000 thro…
severity: high
cvss: 8.6
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N'
cwe:
  - CWE-93
  - CWE-117
vendor: logtape
product: '@logtape/syslog'
affected:
  - '@logtape/syslog >= 2.1.0, <= 2.1.4'
  - '@logtape/syslog >= 2.0.0, < 2.0.14'
  - '@logtape/syslog < 1.3.11'
patched:
  - '@logtape/syslog 2.1.5'
  - '@logtape/syslog 2.0.14'
  - '@logtape/syslog 1.3.11'
published: '2026-08-26'
updated: '2026-09-09'
sourceUpdated: '2026-09-09T21:09:13.080'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-54511'
references:
  - url: >-
      https://github.com/dahlia/logtape/commit/7a6e5b9ddf7915edfff78fa129bc17c979b2a623
    label: security-advisories@github.com
  - url: 'https://github.com/dahlia/logtape/releases/tag/1.3.11'
    label: security-advisories@github.com
  - url: 'https://github.com/dahlia/logtape/releases/tag/2.0.14'
    label: security-advisories@github.com
  - url: 'https://github.com/dahlia/logtape/releases/tag/2.1.5'
    label: security-advisories@github.com
  - url: 'https://github.com/dahlia/logtape/security/advisories/GHSA-8h6h-x5pq-56fq'
    label: security-advisories@github.com
  - url: 'https://github.com/advisories/GHSA-8h6h-x5pq-56fq'
tags:
  - nvd
  - ghsa
  - npm
epss: 0.00306
epssPercentile: 0.23612
aliases:
  - GHSA-8h6h-x5pq-56fq
ecosystem: npm
ingestedAt: '2026-08-26T14:45:08.290Z'
---

## Overview

LogTape is an unobtrusive logging library. Prior to 1.3.11, 2.0.14, and 2.1.5, the @logtape/syslog package's escapeStructuredDataValue() function in packages/syslog/src/syslog.ts does not neutralize C0 control characters from U+0000 through U+001F in structured data values, and formatStructuredData() inserts property keys without validating the RFC 5424 SD-NAME grammar. When includeStructuredData is true, an attacker-controlled newline can terminate an RFC 6587 non-transparent TCP syslog frame and make following bytes appear as a forged RFC 5424 record, while a key containing a closing bracket or other forbidden character can terminate or corrupt the structured-data element. Applications that forward attacker-controlled property values or keys can therefore allow forged records with arbitrary hosts, applications, process identifiers, facilities, or severity levels, undermining downstream collector and SIEM integrity. This issue is fixed in versions 1.3.11, 2.0.14, and 2.1.5.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Package advisory (CVE-2026-54511)

Affected packages:

- `@logtape/syslog >= 2.1.0, <= 2.1.4`
- `@logtape/syslog >= 2.0.0, < 2.0.14`
- `@logtape/syslog < 1.3.11`

Patched in:

- `@logtape/syslog 2.1.5`
- `@logtape/syslog 2.0.14`
- `@logtape/syslog 1.3.11`

Source: https://github.com/advisories/GHSA-8h6h-x5pq-56fq