Malicious PDF — malware analysis report

Static analysis result for SHA-256 a20adac60709969e…

MALICIOUS

PDF

103.5 KB Created: 2021-09-16 12:31:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: a75a536532ab582a5eaf14a99c95472b SHA-1: fb9c975278edac75d5e0d0458d2c1a831684f7d6 SHA-256: a20adac60709969e6636dfb8a208311e2d0b64db651a6b80c85d49963b7e8e74
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML and ClamAV as malicious, with heuristics indicating it functions as a link farm directing users to numerous external PDF files. The presence of embedded URIs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic strongly suggest a phishing or malware distribution attempt, likely initiated via spearphishing. No scripts were extracted, but the nature of the embedded links points to an intent to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

Heuristics 5

  • 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 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://tanhoaphat.vn/userfiles/file/getoli.pdf In PDF document text
    • http://michael-dhom.com/webseiten/file/loxoxizumezatepez.pdfIn PDF document text
    • https://gulf-rope.com/images/bulk_images/files/53004385388.pdfIn PDF document text
    • http://citescolairedeledit.com/include/file/70490550709.pdfIn PDF document text
    • http://eca.or.th/ckfinder/userfiles/files/14230830155.pdfIn PDF document text
    • http://www.supair-lux.hu/ckfinder/userfiles/files/77390484695.pdfIn PDF document text
    • https://twinscooking.nl/twins/userfiles/file/93490926936.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f5be891799---bokirodonefaxapipig.pdfIn PDF document text
    • http://ctm.it/userfiles/file/mazizitizute.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-9-6/20210906130707220408.pdfIn PDF document text
    • http://morard-mcf.fr/data/Files/wedigurakawoguvisu.pdfIn PDF document text
    • http://boathousebrokerage.com/userfiles/file/lojavadivuvega.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613337d1a6a14---nipuvuzobujinir.pdfIn PDF document text
    • http://otestmanager.com/club/data/userfiles/file/20210908120344.pdfIn PDF document text
    • http://raylutickenterprises.com/userfiles/files/gubexemiwikajitosu.pdfIn PDF document text
    • https://oncallanatomist.com/ckfinder/userfiles/files/pevamen.pdfIn PDF document text
    • http://chromavials.com/d/files/lovigowogawuku.pdfIn PDF document text
    • http://tms-technology.com/ckfinder/userfiles/files/resebizedipo.pdfIn PDF document text
    • https://yomadesign.com/userfiles/Proj_Name/files/1395379163.pdfIn PDF document text
    • http://chia4kids.ru/ckfinder/userfiles/files/kuwunokibilemidirolagad.pdfIn PDF document text
    • http://avvocato-callegaro.it/public/file/pibebeletobusivupiwe.pdfIn PDF document text
    • http://kartelabasligi.com/images_upload/files/31614785900.pdfIn PDF document text
    • http://gmkms.net/upfile_editor/2021/files/nesomewolesax.pdfIn PDF document text
    • http://printrun.nl/userfiles/files/fokuzow.pdfIn PDF document text
    • http://icoenergia.com/userfiles/files/kedumukovujerutur.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=how+to+train+your+dragon+3+full+movie+for+freePDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012b6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B6F 19400 bytes
SHA-256: da4fad0b5fd713bc79c49e91de4ba94c8310c302644a084121b361bea315fe5c
font_01_sfnt_off00015e35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15E35 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001764c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1764C 11060 bytes
SHA-256: cc92f9e5dd55927acc6a349afac82000cc85e21c65e11b4a6934ab7948f7b498