Malicious PDF — malware analysis report

Static analysis result for SHA-256 21a2b12b9436121a…

MALICIOUS

PDF

73.3 KB Created: 2021-02-02 16:47:40 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-04-25
MD5: 50dea7275c58d69c81eb4cb3df1b7a3f SHA-1: d05335ed1eb32584c248a773712fe88176ce0bc2 SHA-256: 21a2b12b9436121a00b4a0250b9560cbb9e5a8962ab98710ab036cae28b8c077
196 Risk Score

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://maypoin.ru/wb?keyword=classical%20music%20quiz%20with%20answers PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4444638/normal_60171a65ea0e9.pdfIn PDF document text
    • https://totorososine.weebly.com/uploads/1/3/4/8/134892144/4321303.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4480753/normal_5fe145d131c46.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4422392/normal_5fcec039ce1f7.pdfIn PDF document text
    • https://ruginimurixibiz.weebly.com/uploads/1/3/1/6/131606491/fisilofovubexulerol.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4455208/normal_6011fe15e83ad.pdfIn PDF document text
    • https://kotuposa.weebly.com/uploads/1/3/1/4/131406283/9025368.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4501229/normal_5fcd095d7ab5f.pdfIn PDF document text
    • https://mopijijexexer.weebly.com/uploads/1/3/1/8/131871517/5c215a06d9ab1.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4424666/normal_5fc99762c7909.pdfIn PDF document text
    • https://cdn.sqhk.co/nunamarajop/Bjhjbjf/tulixujovidixexuniza.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/zaxawetawupo/bewamawinibivi.pdfIn PDF document text
    • https://s3.amazonaws.com/nijudow/video_converter_to_mp4_apk_free.pdfIn PDF document text
    • https://s3.amazonaws.com/kovilowab/10288505005.pdfIn PDF document text
    • https://s3.amazonaws.com/batoragubukepo/88179584076.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e26b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE26B 5212 bytes
SHA-256: 505fbcb682142e033b6fbe6d3955dbef323f75a482ae0f7fbe46d8c2de7a0f90
font_01_sfnt_off0000f40e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF40E 10740 bytes
SHA-256: 3f9f9dcbcaf2b1a8a20e56f8810d2cc2497b7041b8d1d527db0bb824ecc25189