Vulnerability · CVE-2026-44742
Postorius through 1.3.13 does not escape HTML in the message subject when rendering it in the Held messages pop-up, as exploited in the wild in May 2026.
Published May 7, 2026 · corrected/updated Jun 17, 2026 · postorius_project postorius · evidence confidence very high
Postorius through 1.3.13 does not escape HTML in the message subject when rendering it in the Held messages pop-up, as exploited in the wild in May 2026.
Grounded briefings
Catalog interpretations for three audiences. Each brief cites ingested metadata and the original advisories below. They are not independent research and they do not invent exploit steps.
Executive
CVE-2026-44742 is a medium public vulnerability record for postorius_project postorius. CISA lists it as known exploited. Published remediation guidance: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable. This summary is a catalog interpretation of the ingested metadata and cites the original advisories below.
System administrator
Identify whether postorius_project postorius is in your estate, then compare installed versions with the affected ranges. Affected packages or ranges on record: postorius project/postorius; postorius_project postorius. Published remediation guidance: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable. Prefer the vendor or distribution advisory linked in Sources before changing production systems. This is a catalog interpretation, not a runbook.
Security analyst
Signals on file: CVSS 6.1 (technical impact); EPSS 0.3% (30-day exploitation probability). CISA lists it as known exploited. Weakness classes: CWE-79. Sources contributing to this record: cve_org, epss, nvd, vulncheck_kev. Public exploit references, when present, are outbound links only and are not proof of active exploitation. This is a catalog interpretation of stored metadata.
Exploitation and remediation
Exploitation evidence
Confirmed in CISA KEV since May 7, 2026. Listed in CISA KEV and VulnCheck KEV.
Patch and remediation
Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Safe detection guidance
Compare installed versions with the affected ranges below and verify the advisory from the original publisher. This site stores metadata and outbound links only; it does not ship exploit code or proof-of-concept payloads.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
May 7, 2026 · CISA KEV
Known exploited
Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
May 7, 2026 · NIST NVD
Detected
Postorius through 1.3.13 does not escape HTML in the message subject when rendering it in the Held messages pop-up, as exploited in the wild in May 2026.
Jun 17, 2026 · NIST NVD
Updated
Postorius through 1.3.13 does not escape HTML in the message subject when rendering it in the Held messages pop-up, as exploited in the wild in May 2026.
Affected
- cpe postorius project/postoriusversion unspecified
- vendor postorius_project postoriusversion unspecified
Sources
- CVE.orgVulnerability recordCVE-2026-44742
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-44742
30-day exploitation probability 0.3%
first.org - NIST NVDVulnerability recordCVE-2026-44742
Postorius through 1.3.13 does not escape HTML in the message subject when rendering it in the Held messages pop-up, as exploited in the wild in May 2026.
nvd.nist.gov - VulnCheck KEVConfirmed exploitationCVE-2026-44742
Postorius through 1.3.13 does not escape HTML in the message subject when rendering it in the Held messages pop-up, as exploited in the wild in May 2026.
vulncheck.com