Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc4cb4730fac9b2e…

MALICIOUS

PDF

77.0 KB Created: 2021-05-05 21:15:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-30
MD5: c5295aeb980f1801f3fbf307ee51b9c9 SHA-1: effa18ee754d2fb7f185f1c015df3ef124676ecb SHA-256: dc4cb4730fac9b2e9f55b08da5020b7ded1c1cdabb202a6064b180a7731232fd
186 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs pointing to external websites, indicative of a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://xajibur.ru/strik?utm_term=what+month+do+you+harvest+wheat PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4416929/normal_5fc6496d1520b.pdfIn PDF document text
    • https://cdn.sqhk.co/bepifopid/Ggjekxp/videos_likee_chistosos.pdfIn PDF document text
    • https://cdn.sqhk.co/kinerufi/jg5NCjc/75031723316.pdfIn PDF document text
    • https://cdn.sqhk.co/wabasenenem/eanhige/the_burger_shop_matawan_menu.pdfIn PDF document text
    • https://cdn.sqhk.co/zabitokepum/yhcFjbe/space_shooter_alien_vs_galaxy_attack_mod.pdfIn PDF document text
    • https://cdn.sqhk.co/galemojubemo/gdehecZ/20360834922.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380088/normal_6042462fe2664.pdfIn PDF document text
    • https://cdn.sqhk.co/joxesinejag/jhvahbM/nexafurisov.pdfIn PDF document text
    • https://cdn.sqhk.co/febowozefu/geiaiiR/zamevitoful.pdfIn PDF document text
    • https://cdn.sqhk.co/bifoligi/VV23heZ/mominabikiba.pdfIn PDF document text
    • https://cdn.sqhk.co/xafiguzi/hjjew4T/sibudisuferugugeluzojilu.pdfIn PDF document text
    • https://cdn.sqhk.co/rotonoba/vFAVjhf/origami_live_wallpaper_apk_xda.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/f8083b6f-033d-4b3b-b196-ea653ef6e93d/water_and_wastewater_engineering_jobs.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1897540c-08e7-4da2-9b2a-60ab2c7c33ab/wovuvasuzurutowidu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9b2c1fc1-0367-4c8b-85a8-57079f14eb7c/how_to_read_penny_stocks.pdfIn PDF document text
    • https://s3.amazonaws.com/purawuma/78101529718.pdfIn PDF document text
    • https://b5c4f4dd-ae1f-4f6a-908c-f463551224e4.filesusr.com/ugd/dafd60_e994f50abd144fb69e2f698ec155bc97.pdf?index=trueIn PDF document text
    • https://fb075467-9d00-46c6-93ac-2b777f5e584b.filesusr.com/ugd/8bcd66_fd5111264d5045f6a31f7e91a6915030.pdf?index=trueIn PDF document text
    • https://17c3d818-7f64-4152-976a-2fa997d7a7be.filesusr.com/ugd/e2c250_68e415c7c6d74bb5b3a6b89547da2f57.pdf?index=trueIn PDF document text
    • https://12350a4d-732a-4148-85a7-4fa27f2a77ec.filesusr.com/ugd/17beed_d7f6e641aea34531b8b99c4e9193678f.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/nabifovu/nazerusewor.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_off0000ef4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF4D 5300 bytes
SHA-256: 6c9390942f1bc956490b79c2604a4df1bb2d66dc4de45b1fc3cd6e4f7b6e519b
font_01_sfnt_off00010141.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10141 11044 bytes
SHA-256: 277cfaa80cc328d19bde71f6c6019197b8e3cd9c1249a3f76829aa8a9018fa1b