# CVE-2026-115507: Vikunja 2.2.0 before 2.7.1 HTML Injection via Notification Email Header
Status: published. Published: 2026-10-22. Updated: 2026-11-04.
Vikunja 2.2.0 before 2.7.1 contains an HTML injection vulnerability in CreateConversationalHeader in pkg/notifications/mail.go that interpolates display names and task and project titles raw into email anchors. Authenticated users can craft titles or display names that close the anchor and inject phishing links into task-comment and task-mention notification emails sent to project members.
## Remediation
- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: VulnCheck) — https://github.com/go-vikunja/vikunja/commit/18ff05932632c65dbc90a88118597989c6af4bf9
## Affected products and versions
- go-vikunja / vikunja (code.vikunja.io/api): ≥ 2.2.0; < 2.7.1 (affected, semver); 2.7.1 (unaffected, semver). Source: CNA: VulnCheck
## Severity and prioritization
- CVSS 4.0: 5.1 (medium); CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N; source: CNA: VulnCheck
- CVSS 3.1: 3.5 (low); CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N; source: CNA: VulnCheck
- CVSS 4.0: 5.1 (medium); CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X; source: NVD: disclosure@vulncheck.com
- CVSS 3.1: 3.5 (low); CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N; source: NVD: disclosure@vulncheck.com
- CISA KEV: No listing in collected sources
- EPSS: 0.20% as of 2026-11-04; percentile 9.49%
- SSVC: exploitation poc; automatable no; technical impact partial; source ADP: CISA-ADP
- Weaknesses: CWE-79
## Exploit evidence
- exploit: https://github.com/go-vikunja/vikunja/security/advisories/GHSA-rp33-8f2m-hm6j (ADP: CISA-ADP)
## References
- https://github.com/go-vikunja/vikunja/security/advisories/GHSA-rp33-8f2m-hm6j (CNA: VulnCheck; vendor-advisory)
- https://github.com/go-vikunja/vikunja/commit/18ff05932632c65dbc90a88118597989c6af4bf9 (CNA: VulnCheck; patch)
- https://github.com/go-vikunja/vikunja/blob/v2.7.0/pkg/notifications/mail.go#L132-L148 (CNA: VulnCheck; technical-description)
- https://github.com/go-vikunja/vikunja/releases/tag/v2.7.1 (CNA: VulnCheck; release-notes)
- https://github.com/go-vikunja/vikunja (CNA: VulnCheck; product)
- https://www.vulncheck.com/advisories/vikunja-2.2.0-before-2.7.1-html-injection-via-notification-email-header (CNA: VulnCheck; third-party-advisory)
- https://github.com/go-vikunja/vikunja/security/advisories/GHSA-rp33-8f2m-hm6j (ADP: CISA-ADP; exploit)
- https://github.com/go-vikunja/vikunja (disclosure@vulncheck.com)
- https://github.com/go-vikunja/vikunja/blob/v2.7.0/pkg/notifications/mail.go#L132-L148 (disclosure@vulncheck.com)
- https://github.com/go-vikunja/vikunja/commit/18ff05932632c65dbc90a88118597989c6af4bf9 (disclosure@vulncheck.com)
- https://github.com/go-vikunja/vikunja/releases/tag/v2.7.1 (disclosure@vulncheck.com)
- https://github.com/go-vikunja/vikunja/security/advisories/GHSA-rp33-8f2m-hm6j (disclosure@vulncheck.com)
- https://www.vulncheck.com/advisories/vikunja-2.2.0-before-2.7.1-html-injection-via-notification-email-header (disclosure@vulncheck.com)
- https://github.com/go-vikunja/vikunja/security/advisories/GHSA-rp33-8f2m-hm6j (134c704f-9b21-4f2e-91b3-4a467353bcc0)
## Provenance
- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-115507; retrieved 2026-11-04; source updated 2026-11-04
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-115507; retrieved 2026-11-04; source updated 2026-11-04
- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-115507; retrieved 2026-11-04; source updated Not reported
Revision: 776ff33d83315836c179e44cc622e1430555da976d4871543a808b9fdd192da2
Canonical: https://y2.dev/cve/CVE-2026-115507
## Agent and API access
Public CVE pages, Markdown, and JSON are free to read without an account or API key.
- Public catalog: https://y2.dev/cve/index.json. Follow nextCursor with the same search, filters, sort, and limit (1–100). A null cursor marks the end.
- WebMCP: search_cve_disclosures, get_cve_disclosure, get_cve_page_markdown, get_y2_cve_access. Available in compatible browsers.
- Cyber API: https://api.y2.dev/api/v2/cyber/cves and https://api.y2.dev/api/v2/cyber/cves/{cveId}.
- Y2 Pro or Elite: create a workspace API key with the intel:cyber scope and send Authorization: Bearer . Setup: https://y2.dev/docs/api/create-key.
- x402: Pay per request without an account or API key. Omit Authorization, read the HTTP 402 PAYMENT-REQUIRED challenge, validate its current requirements, and retry with PAYMENT-SIGNATURE through an authorized payment client. These browser tools never make payments. Guide: https://y2.dev/docs/api/x402.
- OpenAPI: https://y2.dev/api/openapi.yaml. Agent access metadata: https://y2.dev/cve/agent.json.
Collected public records only. Check source status for coverage and freshness.