Malicious PDF — malware analysis report

Static analysis result for SHA-256 994ff11ec803598e…

MALICIOUS

PDF

86.2 KB Created: 2021-09-19 11:26:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: a88b0303bb07754473d1a6f53c9cbea9 SHA-1: fe7f07d4ce034760459786c43a77af1b4d1f0de4 SHA-256: 994ff11ec803598ea104efd37f18fd69acc55a7caf72d879e21bb916dd0d7ed0
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. The heuristics indicate it functions as a link farm, directing users to numerous distinct hosts, with a high number of links per host. While no executable scripts were extracted, the PDF structure and the presence of embedded URLs suggest an attempt to redirect users to malicious sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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 http://factblogs.com/uploaded_files/userfiles/files/jupapekixo.pdf In PDF document text
    • https://www.caissedesecolesdu5eme.fr/backoffice/ckfinder/userfiles/files/96929783071.pdfIn PDF document text
    • http://faurau.com/luodan/images/userfiles/file/giwibagipemetedozefen.pdfIn PDF document text
    • http://www.mustwalge.ee/data/content/files/maviwunerekuso.pdfIn PDF document text
    • http://verynailscm.com/user_img/file/javizifiw.pdfIn PDF document text
    • http://aaronandanthony.com/userfiles/files/muxurojesovekipo.pdfIn PDF document text
    • http://tjjjsh.com/uploads/files/jazuweroja.pdfIn PDF document text
    • http://riverla.vn/uploads/userfiles/file/fipasidurisi.pdfIn PDF document text
    • http://thetestmag.com/userfiles/files/wavoxip.pdfIn PDF document text
    • http://skkouty.cz/ckfinder/userfiles/files/pafuridarurixosit.pdfIn PDF document text
    • https://jobtiara.com/files/files/90589834889.pdfIn PDF document text
    • http://husplaza.hu/editor_up/721095836.pdfIn PDF document text
    • https://cissud.it/uploads/ck_editor/files/bufopajefonefogedesi.pdfIn PDF document text
    • http://urbanelect.com/userfiles/file/58425373591.pdfIn PDF document text
    • http://barudan.hk/UploadFile/file/20210912120459342.pdfIn PDF document text
    • http://www.sosonomo.com/ckfinder/userfiles/files/wotatonowuguwidimube.pdfIn PDF document text
    • http://cmorshomecareassociates.org/uploaded_files/userfiles/files/nuzavuwatisi.pdfIn PDF document text
    • https://cottingham-group.com/cufiles/files/83717767275.pdfIn PDF document text
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16141c55594e9a---98718592152.pdfIn PDF document text
    • http://bowlingkillers.com/imgdb/files/biruriluvawavo.pdfIn PDF document text
    • http://milwaukee.center/userfiles/file/bifoguzer.pdfIn PDF document text
    • http://longarmacademy.net/fckeditor/userfiles/file/pakadipiwaravexukapano.pdfIn PDF document text
    • http://aaas.handyfriendship.com/upload/files/72741852761.pdfIn PDF document text
    • http://businessvaluationapp.com/fck_files/file/37289507686.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=vivavideo+video+makerPDF 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_off0000ec98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC98 10120 bytes
SHA-256: 2fd89729e8287af3afbe300e16421690981ce37b58a08f39a69175e9fb7a9e1e
font_01_sfnt_off00010327.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10327 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011b39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B39 18372 bytes
SHA-256: f9a35ecf28c68b0930012861d034537f801fd4e95bf2c1bbb13abbb7dfaac591