CVE-2021-41868

published 2021-10-04

CVE-2021-41868: OnionShare 2.3 before 2.4 allows remote unauthenticated attackers to upload files on a non-public node when using the --receive functionality.

Priority P2 64 critical 9.8 CVSS 3.1

AV N AC L PR N UI N S U C H I H A H

OnionShare 2.3 before 2.4 allows remote unauthenticated attackers to upload files on a non-public node when using the --receive functionality.

Affected

5 ranges

Vendor	Product	Version range	Fixed in
debian	onionshare	< onionshare 2.5-1 (bookworm)	onionshare 2.5-1 (bookworm)
onionshare	onionshare	>= 0 < 2.5-1	2.5-1
onionshare	onionshare	>= 0 < 2.5-1	2.5-1
onionshare	onionshare	>= 0 < 2.5-1	2.5-1
onionshare	onionshare	>= 2.3 < 2.4	2.4

Detection & IOCs extracted from sources · hover to see the quote

• → Vulnerable functionality is the --receive mode of OnionShare; monitor for unauthenticated file upload attempts to OnionShare nodes running in receive mode on versions 2.3.x before 2.4

• · Vulnerability affects OnionShare versions 2.3 up to (but not including) 2.4; fixed in 2.4+ (Debian packages resolved at 2.5-1) ↗
• · Debian bullseye remains unresolved/open for this CVE; other Debian branches (bookworm, forky, sid, trixie) are fixed at 2.5-1 ↗

CVSS provenance

nvd v3.1 9.8 CRITICAL CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvd v2.0 7.5 HIGH AV:N/AC:L/Au:N/C:P/I:P/A:P

osv 9.8 CRITICAL

vendor_debian 9.8 CRITICAL

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