Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b21803b2b08721b…

MALICIOUS

PDF

76.9 KB Created: 2021-03-09 16:16:19 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: 1da3d8fe8a8316783c5c1a9689ac1c20 SHA-1: 73a917b5ef30af29ec6c947700341e74f1a573ec SHA-256: 1b21803b2b08721b14471dc6ce90d78633d7c5478d1476289fd9173ce574aca4
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains a large number of external links, many hosted on disposable domains, indicating a link farm for SEO manipulation. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to phishing sites or download further malicious content. While no scripts were explicitly extracted, the PDF structure and numerous external URLs point towards a malicious distribution mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://resalured.ru/wix?keyword=ams+2020+hong+kong PDF link annotation
    • http://zedukibawubige.22web.org/92898217182.pdfIn PDF document text
    • https://cdn.sqhk.co/jotoselu/CifhjLY/birds_flap_their_wings.pdfIn PDF document text
    • https://pofekabebo.weebly.com/uploads/1/3/0/7/130739116/9663fa8072f3.pdfIn PDF document text
    • http://vedakedudeloko.22web.org/nefegokoj.pdfIn PDF document text
    • https://cdn.sqhk.co/dusujukakal/jcohejf/best_free_code_editor_windows_10.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454968/normal_6022d89518a68.pdfIn PDF document text
    • https://satisetuxa.weebly.com/uploads/1/3/0/8/130813646/3b69ba833ac483.pdfIn PDF document text
    • https://cdn.sqhk.co/rirakibugo/wtujjhj/lapeketubunu.pdfIn PDF document text
    • https://cdn.sqhk.co/luwanuriwaba/hjoajdR/liverpool_football_wallpaper_for_iphone.pdfIn PDF document text
    • https://sizikipumaxa.weebly.com/uploads/1/3/0/7/130739349/pezunevekun_wedikuledano_kubutivolu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376869/normal_60471679cb1be.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4423195/normal_60168050ae251.pdfIn PDF document text
    • https://cdn.sqhk.co/vekunego/jfjcu3a/fibomurolozilizafawabe.pdfIn PDF document text
    • https://cdn.sqhk.co/defisepeniba/QjjjtbJ/49236949775.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490001/normal_5fd5f96f935d1.pdfIn PDF document text
    • https://cdn.sqhk.co/dovawowo/jhU9xcL/picsart_photo_studio_editor_edition.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://s3.amazonaws.com/juduk/59962269906.pdfIn PDF document text
    • http://vobewegogiz.rf.gd/jakovanapisiwoxi.pdfIn PDF document text
    • http://kafalemanam.epizy.com/bixulimajigigotaxa.pdfIn PDF document text
    • http://kesobikifa.epizy.com/noddy_cartoon_in_english.pdfIn PDF document text
    • https://s3.amazonaws.com/rejiner/que_es_educacion_bilingue_multicultural_e_intercultural.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e4ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4EE 4632 bytes
SHA-256: 35e39dce948b2294a3e048dacf9fa56c8ccfeec8c6f034fab2a47d606c37b28f
font_01_sfnt_off0000f46e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF46E 10436 bytes
SHA-256: fd3b4964d6727d8567cdb1f3de2cf7730cce0e628285cf95165222148a691864
font_02_sfnt_off00011832.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11832 4324 bytes
SHA-256: ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3