How severe is CVE-2022-27926?

CVE-2022-27926 has a CVSS score of 6.1/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2022-27926?

Affected package information for CVE-2022-27926 is not yet fully mapped. Check the official advisory links for details.

How do I fix CVE-2022-27926?

No fixed release is recorded for CVE-2022-27926 yet. Track the upstream advisory, and apply the exposure-reduction steps below in the meantime.

How do I detect CVE-2022-27926 in my code and dependencies?

Identify every host running the affected component and compare the installed build against the fixed version below — for source-built or distro-packaged software the version string, not a lockfile, is the source of truth (`dpkg -l`, `rpm -q`, or the binary's own `--version`).

How do I mitigate CVE-2022-27926 if there is no patch (or I can't update yet)?

Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Is CVE-2022-27926 actively exploited in the wild?

Yes. There are 1 known exploit references for CVE-2022-27926, including 1 in-the-wild exploitation observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2022-27926?

CVE-2022-27926 has an EPSS (Exploit Prediction Scoring System) score of 17.6%, placing it in the 97th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score warrants monitoring and prompt remediation.

Is CVE-2022-27926 in the CISA Known Exploited Vulnerabilities catalog?

Yes. CVE-2022-27926 (Synacor Zimbra Collaboration Suite (ZCS) Cross-Site Scripting (XSS) Vulnerability) was added to CISA's Known Exploited Vulnerabilities (KEV) catalog on 2023-04-03. CISA required all US federal civilian agencies to remediate this vulnerability by 2023-04-24. The required action was: Apply updates per vendor instructions. Being listed in the KEV catalog is the strongest possible confirmation of active exploitation — treat this as a critical priority.

What type of vulnerability is CVE-2022-27926?

CVE-2022-27926 is classified as Cross-site Scripting (XSS) (CWE-79). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

Is there exploit tooling available for CVE-2022-27926?

A Nuclei detection template exists for CVE-2022-27926, meaning automated scanners can fingerprint it. Public exploit tooling significantly increases real-world risk — prioritize patching and ensure detection coverage. Exploit tooling should only ever be used in isolated, authorized testing environments.

When was CVE-2022-27926 published, and has it been updated?

CVE-2022-27926 was published on April 20, 2022 and was last updated on October 24, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🛡️

CISA KEV · ACTIVELY EXPLOITED

MEDIUM severity

CVE-2022-27926 — zm-build

MEDIUM

CVE-2022-27926 is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability. It is in CISA's Known Exploited Vulnerabilities catalog (added 2023-04-03) — treat it as actively exploited and patch now. No vendor fix is recorded yet; mitigation options are listed below.

Published

Apr 20, 2022

Updated

Oct 24, 2026

Affected

1 product

Patched

See advisory

Exploits

1 known

Exploitation data as of Oct 23, 2026 · OSV.dev, NVD, CISA KEV, FIRST.org (EPSS)

Exploitation Status

Actively exploited in the wild

Confirmed by CISA's Known Exploited Vulnerabilities catalog on 2023-04-03. Federal agencies were required to remediate by 2023-04-24.

Exploitation and automatability from CISA (KEV catalog and SSVC triage) for CVE-2022-27926.

EPSS Exploitation Probability

via FIRST.org ↗

17.6%probability of exploitation in next 30 days

Moderate Risk0.00%

Lower risk than most CVEs97th percentile — riskier than 97% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2022-27926 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 395,249 CVEs with a current EPSS score, this one falls in the 10–50% band (highlighted). Counts from FIRST.org, log-scaled.

Description

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.

Affected Products

1 product · 24 configurations

Application

zimbra collaboration suitesynacor

1 version

9.0.0

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

A reflected cross-site scripting (XSS) vulnerability in the /public/laun…

cisa.govCISAApr 2023

Detection & mitigation playbook

Vulnerability

Detect
Identify every host running the affected component and compare the installed build against the fixed version below — for source-built or distro-packaged software the version string, not a lockfile, is the source of truth (`dpkg -l`, `rpm -q`, or the binary's own `--version`).
Remediation status
No fixed release is recorded for CVE-2022-27926 yet. Track the upstream advisory, and apply the exposure-reduction steps below in the meantime.
Mitigate without a patch
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

How to detect CVE-2022-27926

A community-maintained Nuclei template exists for this CVE. You can scan for it directly:

nuclei -id cve-2022-27926 -u https://target

Template: Zimbra Collaboration (ZCS) - Cross Site Scripting
Severity: medium
Impact: Successful exploitation of this vulnerability could allow an attacker to execute arbitrary script code in the context of the victim's browser, potentially leading to session hijacking, defacement, or theft of sensitive information.
Remediation: Apply the latest security patches or updates provided by Zimbra to fix the XSS vulnerability.

Template by ProjectDiscovery nuclei-templates (rootxharsh, iamnoooob, pdresearch), MIT licensed. View the full template. Scan only systems you are authorised to test.

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is CVE-2022-27926 in your dependencies?

Find it across , including transitive dependencies.

Scan my dependencies How O3 SCA works

CVSS Score

6.1/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Raw vector

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

CWE Classification

CWE-79Cross-site Scripting (XSS)

Weaponization

Timeline

Disclosed

Apr 20, 2022

KEV added

Apr 3, 2023

First exploit

Apr 3, 2023

Last updated

Oct 24, 2026

Identifiers

CVE-2022-27926

References

Advisorygithub.com Advisorynvd.nist.gov Webwiki.zimbra.com Webwiki.zimbra.com Webwiki.zimbra.com Webcisa.gov

Related vulnerabilities

This CVE is medium severity; 4 of 8 other CVEs with CWE-79 are rated as high or higher (top: critical).

CVE-2026-114061GHSA-2rqm-h6hv-g79vCVE-2026-115897CVE-2026-114128CVE-2026-63430GHSA-c6gr-qvv4-5v3fGHSA-cg2g-xh64-v4q7CVE-2026-114130Browse all CWE-79

Provenance

Sources

OSV.devNVDCISA KEVFIRST.org (EPSS)

Last verifiedOct 24, 2026