Vector: Arbitrary file write in the file sink via templated path (path traversal).
Collected exploitation and prediction evidence
Risk source coverageCISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.
No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.
cve-program · CVE-2026-77621
PublishedVector is a high-performance observability data pipeline. From 0.10.0 until 0.57.0, the file sink renders its templated path from event fields and opens the result without confining it to an intended directory. When an untrusted source supplies an event field used by the path template, the value can contain an absolute path or parent-directory traversal, causing Vector to create parent directories and create or overwrite files outside the intended location with the Vector process privileges. The resulting file write can modify sensitive files and can lead to code execution when a scheduled task, authorization file, or subsequently executed script is targeted. This issue is fixed in version 0.57.0.
- Source published
- 22 Sep 2026 15:19:19 UTC
- Source modified
- 25 Sep 2026 23:32:37 UTC
- Observed here
- 23 Oct 2026 15:48:27 UTC
- Source terms
- CVE Program Terms of Use
Original source record · Cite this exact observation · Complete original publisher JSON
This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.
CVSS 4.0 · 9.3 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:H/SI:H/SA:H