# CVE-2026-121517: IrfanView TIFF Wang Annotation heap-based overflow

Status: published. Published: 2026-11-03. Updated: 2026-11-03.

A vulnerability was detected in IrfanView 4.76.0.0 on Win64. Affected by this vulnerability is an unknown functionality of the component TIFF Wang Annotation Handler. Performing a manipulation results in heap-based buffer overflow. The attack is possible to be carried out remotely. The complexity of an attack is rather high. The exploitation appears to be difficult. The exploit is now public and may be used. It is recommended to apply a patch to fix this issue. The vendor confirms: "[T]he TIF-Annotations option is OFF by default. Means, normal users are not affected ... the danger level for this is low".

## Remediation

No remediation reported in collected sources

## Affected products and versions

- n/a / IrfanView: 4.76.0.0 (affected). Source: CNA: VulDB

## Severity and prioritization

- CVSS 4.0: 2.3 (low); CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P; source: CNA: VulDB

- CVSS 3.1: 5 (medium); CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:L/E:P/RL:O/RC:C; source: CNA: VulDB

- CVSS 3.0: 5 (medium); CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:L/E:P/RL:O/RC:C; source: CNA: VulDB

- CVSS 2.0: 5.1 (medium); AV:N/AC:H/Au:N/C:P/I:P/A:P/E:POC/RL:OF/RC:C; source: CNA: VulDB

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-122, CWE-119

## Exploit evidence

- exploit: https://github.com/dwBruijn/CVEs/blob/main/IrfanView/TIFF/Tiff_Wang.md (CNA: VulDB)

## References

- https://vuldb.com/vuln/430288 (CNA: VulDB; vdb-entry)

- https://vuldb.com/vuln/430288/cti (CNA: VulDB; signature, permissions-required)

- https://vuldb.com/cve/CVE-2026-121517 (CNA: VulDB; third-party-advisory)

- https://vuldb.com/submit/1018543 (CNA: VulDB; third-party-advisory)

- https://github.com/dwBruijn/CVEs/blob/main/IrfanView/TIFF/Tiff_Wang.md (CNA: VulDB; exploit)

- https://www.irfanview.com/ (CNA: VulDB; product)

## Provenance

- CNA: VulDB: https://www.cve.org/CVERecord?id=CVE-2026-121517; retrieved 2026-11-03; source updated 2026-11-03

Revision: 4572fbad5108cbc21692040d588d71e4ba4b678a32efb36c7aa5977bdbb4a75a

Canonical: https://y2.dev/cve/CVE-2026-121517

## 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 <Y2_API_KEY>. 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.