CVE-2026-50057: Zimbra Collaboration Suite Local Privilege Escalation via Unrestricted Postfix Sudo Permissions
Noroxi assessment
Priority: Monitor (action score 31/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.26% (FIRST EPSS).
- Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
- According to the record, no fixed version is available yet.
Low priority for now. Update when a fix is released; follow the vendor's advisory.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
A local privilege escalation vulnerability in the Zimbra Collaboration Suite (ZCS) MTA package allows the Unix zimbra account to execute arbitrary commands as root. The installed sudo policy permits passwordless root execution of Postfix administration commands without restricting their arguments. An attacker can select a zimbra-controlled daemon_directory in the Postfix configuration and invoke postfix set-permissions, causing Postfix to execute the attacker's post-install program as root. The Postfix configuration directory is also writable by zimbra, so restricting postconf alone does not remove the execution path. Exploitation requires local command execution as zimbra on an MTA node. ZCS 10.1.16 and 10.1.21 are affected.
- Published
- Oct 23, 2026
- Updated
- Oct 24, 2026
- EPSS
- 0.2% · 18th percentile
- CWE
- CWE-732
Report tools
Action score
31
Monitor
Low priority for now.
- CVSS
- 31 / 40 · 7.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.2%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · rapid7
- 7.8
- NVD has not scored this yet; the score shown is the CNA’s.
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- No fixed version yet
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
—
Versions reported by the vendor
Affected version ranges reported by the assigning authority (rapid7). Independent of NVD's CPE analysis and usually ahead of it.
Zimbra Zimbra Collaboration Suite
- up to and including 10.1.21affected · semver
Same product
zimbra: all recordsOther highest-scoring records for the same primary product.
- CVE-2015-7610Cross-site request forgery (CSRF) vulnerability in the login form in Zimbra Collaboration Suite (aka ZCS) before 8.6.0 Patch 10, 8.7.x befor35Monitor
- CVE-2026-93639Zimbra Collaboration Suite Missing Authorization in ConfigureZimlet Enables Delegated Administrator Privilege Escalation34Monitor
- CVE-2026-50053Zimbra Collaboration Suite RestFilter Request Attribute Override via Unauthenticated URL Parameters34Monitor
Published before and after this one in the same product
- ← EarlierCVE-2026-115786Oct 23, 2026 · Zimbra Collaboration Suite Shared-File Mailbox Quota Accounting Error Enables Quota Exhaustion26Monitor
- ← EarlierCVE-2026-50056Oct 23, 2026 · Zimbra Collaboration Suite Local Privilege Escalation via zmmailboxdmgr JVM Argument Injection31Monitor
- Later →CVE-2026-93627Oct 23, 2026 · Zimbra Collaboration Suite Calendar Processing Authentication Bypass via Forged iCalendar CANCEL/REQUEST Organizer21Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
No fix version is recorded for this entry. Check the references for vendor advisories.
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2026-936400 days apartZimbra Collaboration Suite Local Privilege Escalation via Unrestricted zmunbound Sudo Configuration31Monitor
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
- CVE-2026-936270 days apartZimbra Collaboration Suite Calendar Processing Authentication Bypass via Forged iCalendar CANCEL/REQUEST Organizer21Monitor
- CVE-2026-936280 days apartZimbra Collaboration Suite Calendar Processing Authentication Bypass via Forged iCalendar REPLY Attendee Response21Monitor
- CVE-2026-936290 days apartZimbra Collaboration Suite Calendar Processing Authentication Bypass via Forged iCalendar REQUEST Organizer Identity21Monitor
- CVE-2026-936379 days apartZimbra Collaboration Suite GraphQL Batched Authentication Bypasses Pre-Auth Rate Limiting14Monitor
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Someone with local access to the system can trigger it.
- A low-privileged account is enough.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
CWE-732 · Incorrect Permission Assignment for Critical ResourceCVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
- Accessing Functionality Not Properly Constrained by ACLsCAPEC-1likelihood: High · High
- Privilege AbuseCAPEC-122likelihood: High · Medium
- Directory IndexingCAPEC-127likelihood: High · Medium
- Using Malicious FilesCAPEC-17likelihood: High · Very High
- Exploiting Incorrectly Configured Access Control Security LevelsCAPEC-180likelihood: High · Medium
- Signing Malicious CodeCAPEC-206Very High
- Hijacking a privileged processCAPEC-234Medium
- Reusing Session IDs (aka Session Replay)CAPEC-60likelihood: High · High
ATT&CK techniques
- File and Directory DiscoveryT1083
- Access Token Manipulation:Token Impersonation/TheftT1134.001
- Server Software Component: Terminal Services DLLT1505.005
- Abuse Elevation Control MechanismT1548
- Use Alternate Authentication Material:Web Session CookieT1550.004
- Subvert Trust Controls:Code SigningT1553.002
- Compromise Client Software BinaryT1554
- Hijack Execution Flow:Executable Installer File Permissions WeaknessT1574.005
- Hijack Execution Flow: ServicesFile Permissions WeaknessT1574.010
Change log
- SSVC exploitation— → none
- Exploit maturity— → none
For records you follow, these changes also arrive as notifications. →
References
Show all references (1 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.