FKIE_CVE-2026-77353

Vulnerability from fkie_nvd - Published: 2026-08-31 22:17 - Updated: 2026-08-31 22:17
Severity
4.6 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
Summary
Wallos is an open-source, self-hostable personal subscription tracker. Prior to version 5.0.0, Wallos allows authenticated users to inject arbitrary iCalendar properties and events into their exported .ics feed by embedding raw CRLF sequences in subscription names or notes. Because the input validation layer only encodes HTML metacharacters but never strips newlines, and the export layer decodes those entities back before writing iCal output, an attacker with any valid account can craft a subscription whose name breaks out of the current VEVENT block and inserts fully attacker-controlled calendar events — including spoofed organizers, arbitrary email addresses in ATTENDEE properties, and misleading event content — into any calendar application subscribed to that feed. This issue has been patched in version 5.0.0.
References
security-advisories@github.comhttps://github.com/ellite/Wallos/commit/11eaf402e841a628c68a805694227ce66c45f6f3
security-advisories@github.comhttps://github.com/ellite/Wallos/releases/tag/v5.0.0
security-advisories@github.comhttps://github.com/ellite/Wallos/security/advisories/GHSA-q2r8-m9wm-5547
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "Wallos",
          "vendor": "ellite",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 5.0.0"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Wallos is an open-source, self-hostable personal subscription tracker. Prior to version 5.0.0, Wallos allows authenticated users to inject arbitrary iCalendar properties and events into their exported .ics feed by embedding raw CRLF sequences in subscription names or notes. Because the input validation layer only encodes HTML metacharacters but never strips newlines, and the export layer decodes those entities back before writing iCal output, an attacker with any valid account can craft a subscription whose name breaks out of the current VEVENT block and inserts fully attacker-controlled calendar events \u2014 including spoofed organizers, arbitrary email addresses in ATTENDEE properties, and misleading event content \u2014 into any calendar application subscribed to that feed. This issue has been patched in version 5.0.0."
    }
  ],
  "id": "CVE-2026-77353",
  "lastModified": "2026-08-31T22:17:20.743",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 4.6,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.1,
        "impactScore": 2.5,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-08-31T22:17:20.743",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/ellite/Wallos/commit/11eaf402e841a628c68a805694227ce66c45f6f3"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/ellite/Wallos/releases/tag/v5.0.0"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/ellite/Wallos/security/advisories/GHSA-q2r8-m9wm-5547"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-74"
        },
        {
          "lang": "en",
          "value": "CWE-116"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Primary"
    }
  ]
}



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