CVE-2026-108839CWE-59

CVE-2026-108839

Medium · published October 11, 2026

CVSS v3.1
4.2
EPSS
0%
Percentile
15.6
In the wild
Unconfirmed
What it is

thClaws through 0.141.0 contains a link-following vulnerability in the post_inputs handler of the v1 API POST /v1/inputs endpoint that allows writes outside the workspace by following symlinks. Attackers who plant a symlink under the allowed inputs/ prefix can cause later authenticated uploads to write or truncate files outside the workspace with daemon privileges.

The record
Technical detail
CVSS v3.1
4.2 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:L
CVSS v4.0
2.3 · CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N
EPSS
0.00251 · 15.6th percentile
Weakness
CWE-59 · Improper Link Resolution Before File Access ('Link Following')
Published
2026-10-11T18:17Z
References (4)
https://github.com/thClaws/thClaws · [email protected]https://github.com/thClaws/thClaws/blob/v0.141.0/crates/core/src/api_v1/artifacts.rs#L335-L420 · [email protected]https://hackmd.io/@1ExmmukzRMWN7B4gQ4W-4Q/thclaws-api-inputs-symlink-escape · [email protected]https://www.vulncheck.com/advisories/thclaws-through-0.141.0-symlink-following-file-write-via-post-v1-inputs · [email protected]
EPSS history
Timeline
  • 13 OCT 03:28Z
    EPSS moved — → 0%
    epss
  • 11 OCT 13:26Z
    thClaws through 0.141.0 Symlink Following File Write via POST /v1/inputs
    cvelistv5
  • 11 OCT 13:26Z
    thClaws through 0.141.0 Symlink Following File Write via POST /v1/inputs
    cvelistv5