CVE-2026-77353Public exploitNetwork attack vector

Calendar event injection via unescaped CRLF sequences

Published Aug 31, 2026 · Updated Sep 3, 2026

iCalendar injection in ellite Wallos before 5.0.0 allows remote authenticated users to insert events into exported calendar feeds. Export endpoints decode stored subscription names and notes, then place them into iCalendar properties without escaping CRLF line delimiters. Any valid account can create peer-level VEVENT entries that subscribed calendar clients display as legitimate reminders, including spoofed organizer and attendee data.

CVSS severity4.6
Medium
EPSS probability0.17%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

iCalendar injection in ellite Wallos before 5.0.0 allows remote authenticated users to insert events into exported calendar feeds. Export endpoints decode stored subscription names and notes, then place them into iCalendar properties without escaping CRLF line delimiters. Any valid account can create peer-level VEVENT entries that subscribed calendar clients display as legitimate reminders, including spoofed organizer and attendee data.

The record

CVE
CVE-2026-77353
Published
Aug 31, 2026
Updated
Sep 3, 2026
Vendor
ellite
Product
Wallos
Classifications
CWE-116, CWE-74
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 31, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 3, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 5.0.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

ellite · Wallosversion=< 5.0.0

Published CVSS scores

4.6GitHubCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-116Improper Encoding or Escaping of Output
CWE-74Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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