High [CVE-2026-81727] Filesystem containment bypass allows local file overwrite
This high-severity Red Hat Linux advisory covers CVE-2026-81727 affecting Exploit Intelligence, Lightspeed Core, OpenShift Lightspeed.
Android app · Google Play
Monitor future Red Hat Linux CVEs from your phone.
Choose a whole vendor or a precise platform, then receive matching security advisories by phone notification, email, or both. Coverage follows 32 official vendor sources and 160+ reviewed platform categories.
Summary
NLTK versions before 3.10.3 contain a filesystem containment bypass vulnerability in the Downloader.download and Downloader.incr_download methods that allows attackers to overwrite files outside the install root through pre-existing hardlinks.
Attackers with write access to a shared downloader directory can create hardlinks pointing to outside-root files that are then overwritten during normal package extraction, mutating files outside the intended install tree. A flaw was found in NLTK.
This vulnerability, a filesystem containment bypass, allows a local attacker with write access to a shared downloader directory to create special links (hardlinks) that point to files outside the intended installation area.
When a package is extracted, these hardlinks can cause files outside the NLTK installation to be overwritten, leading to unauthorized modification or corruption of data. Red Hat severity: Important — CVSS 7.1 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H).
Weakness: CWE-59. Affected Red Hat products: Exploit Intelligence; Lightspeed Core; OpenShift Lightspeed; Red Hat Ansible Automation Platform 2; Red Hat OpenShift AI (RHOAI).
Red Hat does not currently list a fixing RHSA for this CVE.
- < 3.10.3
Official advisory · high-confidence parse· fetched 1 hour ago·verify at source
Fixed versions
No fixed release is recorded yet. That does not prove no patch exists — confirm against the vendor advisory.
Official advisory · high-confidence parse· fetched 1 hour ago·verify at source
Mitigation
The source record does not include mitigation steps. That is not a statement that no fix exists — read the vendor advisory below for the authoritative guidance.
Official advisory · high-confidence parse· fetched 1 hour ago·verify at source
Discussion(0)
No comments yet. Share field notes, upgrade gotchas, or questions — verify against the vendor advisory before acting on community advice.
Sign in to join the discussion.