@logtape/syslog: syslog log injection via unescaped control characters and unvalidated SD-NAME keys
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · High · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub.
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 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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| dahlia | logtape | before 1.3.11; 2.0.0 to before 2.0.14; 2.1.0 to before 2.1.5 | 1.3.11, 2.0.14, 2.1.5 | Patch available | CNA |
| — | @logtape/syslog (npm) | 2.1.0 to before 2.1.5 | 2.1.5 | Patch available | GHSA-8h6h-x5pq-56fq |
| — | @logtape/syslog (npm) | 2.0.0 to before 2.0.14 | 2.0.14 | Patch available | GHSA-8h6h-x5pq-56fq |
| — | @logtape/syslog (npm) | before 1.3.11 | 1.3.11 | Patch available | GHSA-8h6h-x5pq-56fq |
- logtape Vendordahlia Affected before 1.3.11; 2.0.0 to before 2.0.14; 2.1.0 to before 2.1.5 Fixed in 1.3.11, 2.0.14, 2.1.5 Patch available CNA
- @logtape/syslog (npm) Vendor— Affected 2.1.0 to before 2.1.5 Fixed in 2.1.5 Patch available GHSA-8h6h-x5pq-56fq
- @logtape/syslog (npm) Vendor— Affected 2.0.0 to before 2.0.14 Fixed in 2.0.14 Patch available GHSA-8h6h-x5pq-56fq
- @logtape/syslog (npm) Vendor— Affected before 1.3.11 Fixed in 1.3.11 Patch available GHSA-8h6h-x5pq-56fq
Remediation
- Fix · CNA logtape (dahlia) Fixed in 1.3.11, 2.0.14, 2.1.5
- Fix · GHSA-8h6h-x5pq-56fq @logtape/syslog (npm) Fixed in 2.1.5 Advisory →
- Fix · GHSA-8h6h-x5pq-56fq @logtape/syslog (npm) Fixed in 2.0.14 Advisory →
- Fix · GHSA-8h6h-x5pq-56fq @logtape/syslog (npm) Fixed in 1.3.11 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-54511
- 2026-10-03 Alias added: GHSA-8h6h-x5pq-56fq
References
Other 6
- https://github.com/dahlia/logtape/security/advisories/GHSA-8h6h-x5pq-56fq
- https://github.com/dahlia/logtape/commit/7a6e5b9ddf7915edfff78fa129bc17c979b2a623
- https://github.com/dahlia/logtape/releases/tag/1.3.11
- https://github.com/dahlia/logtape/releases/tag/2.0.14
- https://github.com/dahlia/logtape/releases/tag/2.1.5
- https://github.com/dahlia/logtape
More dahlia vulnerabilities
- TI-2025-17006 Fedify has an Infinite loop and Blind SSRF found inside the Webfinger mechanism CVSS 3.1MEDIUM 5.4
- TI-2024-26611 Fedify vulnerable to allowing access to internal network resources CVSS 3.1HIGH 7.2
Sources
- CVE-2026-54511 · CVE Program
- CVE-2026-54511 · NVD
- FIRST EPSS
- GHSA-8h6h-x5pq-56fq · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences