CVE-2026-54511@logtape/syslog: syslog log injection via unescaped control characters and unvalidated SD-NAME keys
- 8.6HighCVSS base score
- 0.48%Exploitation in 30 daysEPSS · top 58% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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.
Timeline
ID reserved
By GitHub_M
- 2 months later
· 2 months later
Published
- 1 day later
· 1 day later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | High8.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N |
| NVDNVD · Deferred | 3.1 | High8.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N |
- EPSS (exploitation in 30 days)
- 0.48% · top 58% of all CVEs (14 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.6.
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- npm@logtape/syslogGHSA-8h6h-x5pq-56fq (opens in a new tab)
References
References5
- https://github.com/dahlia/logtape/security/advisories/GHSA-8h6h-x5pq-56fq (opens in a new tab)x_refsource_CONFIRM
- https://github.com/dahlia/logtape/commit/7a6e5b9ddf7915edfff78fa129bc17c979b2a623 (opens in a new tab)x_refsource_MISC
- https://github.com/dahlia/logtape/releases/tag/1.3.11 (opens in a new tab)x_refsource_MISC
- https://github.com/dahlia/logtape/releases/tag/2.0.14 (opens in a new tab)x_refsource_MISC
- https://github.com/dahlia/logtape/releases/tag/2.1.5 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-66563 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-8h6h-x5pq-56fq (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-54511)Record last updated .