PT-2022-6377 · Nextcloud · Nextcloud Mail

Supr4S · Published 2022-12-21 · Updated 2023-02-15 · CVE-2023-23943

Positive Technologies (AI Summary)

CVSS v3.1

5.0

Medium

Base vector

AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N

Name of the Vulnerable Software and Affected Versions Nextcloud mail versions prior to 1.15.0 Nextcloud mail versions prior to 2.2.2

Description The issue is related to insufficient validation of incoming requests in the Nextcloud mail client, allowing a remote attacker to scan internal services and servers accessible from the local network of the Nextcloud server. The SMTP, IMAP, and Sieve host fields are affected, enabling the scanning of internal services and servers reachable from within the local network of the Nextcloud Server.

Recommendations For versions prior to 1.15.0, upgrade to 1.15.0 to resolve the issue. For versions prior to 2.2.2, upgrade to 2.2.2 to resolve the issue. As a temporary workaround, consider completely disabling the Nextcloud mail app until a patch is available.

Exploit

Fix

SSRF

Weakness Enumeration

CWE-918

Related Identifiers

BDU:2023-01082

CVE-2023-23943

GHSA-8GCX-R739-9PF6

Affected Products

Nextcloud Mail

References · 11

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/23xxx/CVE-2023-23943.json · Exploit
• 🔥 https://hackerone.com/reports/1736390 · Exploit
• 🔥 https://hackerone.com/reports/1746582 · Exploit
• 🔥 https://hackerone.com/reports/1741525 · Exploit
• https://github.com/nextcloud/mail/pull/7796 · Patch
• https://github.com/nextcloud/security-advisories/security/advisories/GHSA-8gcx-r739-9pf6 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2023-23943 · Security Note
• https://bdu.fstec.ru/vul/2023-01082 · Security Note
• https://osv.dev/vulnerability/CVE-2023-23943 · Vendor Advisory
• https://t.me/cvenotify/44363 · Telegram Post
• https://t.me/cibsecurity/57618 · Telegram Post