CVE-2022-27926

A reflected cross-site scripting (XSS) vulnerability in the /public/launchNewWindow.jsp component of Zimbra Collaboration (aka ZCS) 9.0 allows unauthenticated attackers to execute arbitrary web script or HTML via request parameters.

CVSS: 6.1Mediumscored by CISA
Exploited in the wild: Yes, in CISA KEV since 3 Apr 2023CISA deadline for US federal agencies: 24 Apr 2023
EPSS: 17.6%chance of exploitation in the next 30 daystop 3% of scored CVEsFIRST score of 11 Nov 2026
Fix: Patch availablesee the advisories in the references
Published: 21 Apr 2022analysed here 12 Nov 2026

Do first. Apply updates per vendor instructions. (CISA's required action for this KEV entry)

Summary

Triage

Attack surface: Client-side
Exploitable: At runtime
Attack vector: network
Weakness: CWE-79 Cross-Site Scripting (XSS)
Can a WAF block it?: Yes. See why

The summary, impact and action text on this page are written by our AI analysis pipeline, or taken from the NVD description when a CVE was imported from NVD. They are not the vendor's wording: check them against the sources. A longer AI executive summary and technical analysis are generated for signed-in accounts on the Max plan.

Affected products

Products named in our analysis

synacor:zimbra_collaboration_suite

Fix and mitigation

WAF and other mitigations

Can a WAF block it? Yes. The vulnerability is a reflected cross-site scripting in an HTTP request to a specific URL with malicious parameters. A WAF can detect and block requests with suspicious script or HTML content in these parameters. A WAF rule can match /public/launchNewWindow.jsp request parameters containing script or HTML injection. No tracked WAF vendor has published a rule for this CVE yet, so you would write it yourself.

What a custom rule would match: /public/launchNewWindow.jsp request parameters containing script or HTML injection

Also consider: patch · custom WAF rule · CSP · output encoding

Based on an AI reading of the CVE description, and no vendor rule found yet. We check Cloudflare, AWS, Google Cloud Armor and Azure; for Akamai, Imperva, Fastly, F5, ask your vendor.

Remediation steps (AI-written)

Step-by-step remediation is generated for accounts on the Max plan, for CVEs that match a technology in their stack. Add this technology to your stack to see the fix checklist.

Exploitation evidence

CISA KEV catalog: Listed since 3 Apr 2023.
CISA due date: 24 Apr 2023, the remediation deadline for US federal agencies
CISA required action: Apply updates per vendor instructions.
Public exploit code: Detection templates only, no public exploit found: 1 Nuclei template
CISA SSVC: exploitation active, automatable no, technical impact partialAssessed by CISA 29 Jan 2025 (SSVC 2.0.3). Exploitation is none, poc (public proof of concept) or active.

Nuclei

Zimbra Collaboration (ZCS) - Cross Site Scriptingdetection template, medium

Listed so you can judge urgency, not as a recommendation to run anything. GitHub “proofs of concept” are unvetted: some are fake or carry malware. Exploit-DB marks the entries its staff verified.

Timeline

21 Apr 2022Published
3 Apr 2023Added to CISA KEV (exploited in the wild)347 days (about 12 months) later
24 Apr 2023CISA remediation due date (US federal agencies)21 days later
29 Jan 2025CISA SSVC assessment: exploitation active647 days (about 2 years) later
21 Oct 2025CVE record last updated265 days (about 9 months) later
12 Nov 2026Analysed by vulneraibility.com387 days (about 1 year) later

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Metric	Value	What it means
Attack vector	NetworkReachable over the internet or any routable network.	Reachable over the internet or any routable network.
Attack complexity	LowRepeatable attack, no special conditions.	Repeatable attack, no special conditions.
Privileges required	NoneThe attacker needs no prior access.	The attacker needs no prior access.
User interaction	RequiredA victim must click, open or otherwise cooperate.	A victim must click, open or otherwise cooperate.
Scope	ChangedImpact crosses a security boundary into other components.	Impact crosses a security boundary into other components.
Confidentiality	LowPartial data disclosure.	Partial data disclosure.
Integrity	LowLimited modification possible.	Limited modification possible.
Availability	NoneThe service stays up.	The service stays up.

Common questions

Is CVE-2022-27926 being exploited?

Yes. CVE-2022-27926 appears in CISA's Known Exploited Vulnerabilities catalog, which means exploitation in the wild has been confirmed and reported. Treat it as active rather than theoretical, and patch it ahead of higher-scoring vulnerabilities that carry no exploitation evidence.

How severe is CVE-2022-27926?

CVE-2022-27926 is rated Medium with a CVSS score of 6.1. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.

Is there a patch for CVE-2022-27926?

Yes. A fix has been recorded for CVE-2022-27926. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.

What does CVE-2022-27926 affect?

CVE-2022-27926 affects synacor:zimbra_collaboration_suite. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.

Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.

References

NVD CVE.org CVE Details Source

4 references in the CVE record, grouped by the tags the record gives them.

Where the data on this page comes from

CVE List (CVE.org): description, affected versions, references; CVE Terms of Use
NVD: CVSS and CPE data
CISA KEV catalog: exploitation, date added, due date
CISA Vulnrichment (ADP): SSVC decision points
FIRST EPSS: exploit probability and percentile
Nuclei templates: detection templates

Summary, impact and triage tags: written by our AI analysis pipeline from the sources above. Check them against the sources.

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