CVE-2026-33371 | Zimbra Collaboration Suite 10.0/10.1 Exchange Web Service xml external entity reference

VDB-352083 · CVE-2026-33371 · GCVE-0-2026-33371 ZIMBRA COLLABORATION SUITE 10.0/10.1 EXCHANGE WEB SERVICE XML EXTERNAL ENTITY REFERENCE HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 6.3 $0-$5k 1.97+ Summaryinfo A vulnerability marked as problematic has been reported in Zimbra Collaboration Suite 10.0/10.1. The affected element is an unknown function of the component Exchange Web Service. Performing a manipulation results in xml external entity reference. This vulnerability was named CVE-2026-33371. The attack may be initiated remotely. There is no available exploit. Detailsinfo A vulnerability, which was classified as critical, was found in Zimbra Collaboration Suite 10.0/10.1. This affects an unknown code of the component Exchange Web Service. The manipulation with an unknown input leads to a xml external entity reference vulnerability. CWE is classifying the issue as CWE-611. The product processes an XML document that can contain XML entities with URIs that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is: An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1. An XML External Entity (XXE) vulnerability exists in the Zimbra Exchange Web Services (EWS) SOAP interface due to improper handling of XML input. An authenticated attacker can submit crafted XML data that is processed by an XML parser with external entity resolution enabled. Successful exploitation may allow disclosure of sensitive local files from the server. It is possible to read the advisory at wiki.zimbra.com. This vulnerability is uniquely identified as CVE-2026-33371 since 03/19/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 03/20/2026). There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product. Productinfo Type Groupware Software Vendor Zimbra Name Collaboration Suite Version 10.0 10.1 CPE 2.3info 🔒 🔒 CPE 2.2info 🔒 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv3info VulDB Meta Base Score: 6.3 VulDB Meta Temp Score: 6.3 VulDB Base Score: 6.3 VulDB Temp Score: 6.3 VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv2info Vector Complexity Authentication Confidentiality Integrity Availability Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock VulDB Base Score: 🔒 VulDB Temp Score: 🔒 VulDB Reliability: 🔍 Exploitinginfo Class: Xml external entity reference CWE: CWE-611 / CWE-610 CAPEC: 🔒 ATT&CK: 🔒 Physical: No Local: No Remote: Yes Availability: 🔒 Status: Not defined Price Prediction: 🔍 Current Price Estimation: 🔒 0-Day Unlock Unlock Unlock Unlock Today Unlock Unlock Unlock Unlock Threat Intelligenceinfo Interest: 🔍 Active Actors: 🔍 Active APT Groups: 🔍 Countermeasuresinfo Recommended: no mitigation known Status: 🔍 0-Day Time: 🔒 Timelineinfo 03/19/2026 CVE reserved 03/20/2026 +1 days Advisory disclosed 03/20/2026 +0 days VulDB entry created 03/20/2026 +0 days VulDB entry last update Sourcesinfo Advisory: wiki.zimbra.com Status: Confirmed CVE: CVE-2026-33371 (🔒) GCVE (CVE): GCVE-0-2026-33371 GCVE (VulDB): GCVE-100-352083 Entryinfo Created: 03/20/2026 15:47 Changes: 03/20/2026 15:47 (54) Complete: 🔍 Cache ID: 99:A15:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸