Malicious PDF — malware analysis report

Static analysis result for SHA-256 f78bc68f95007d71…

MALICIOUS

PDF

70.9 KB Created: 2021-10-01 00:09:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: c21a2facf0dd32133ad7f08f1a7bb310 SHA-1: 2942f9dfcf017e80bad95680e23a7ab096f1a0e8 SHA-256: f78bc68f95007d71a003fd9618cf853331af874e3cf628733e94b3765c95236e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs that form a link farm, a common technique for distributing phishing lures or directing users to malicious sites. Heuristics indicate these links are hosted on disposable or compromised domains, increasing the likelihood of malicious intent. The ML classifier and ClamAV detection strongly suggest this PDF is malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://krisoc.ru/uplcv?utm_term=bharat+option+apk+download PDF link annotation
    • http://style4.allwebeasy.com/userfiles/files/72512423622.pdfIn PDF document text
    • https://avenue102.com/uploads/file/vebimuxipagunow.pdfIn PDF document text
    • http://chernogolovka.inhome360.ru/admin/ckfinder/userfiles/files/fodebujevoxusupudufabew.pdfIn PDF document text
    • https://dolphinsolutions.net/ckfinder/userfiles/files/31944899425.pdfIn PDF document text
    • http://daiichihr.com/uploads/news_file/gutabixiwoxulorab.pdfIn PDF document text
    • https://rougezenekar.hu/files/file/gekebivi.pdfIn PDF document text
    • http://abwlargo.com/uploads/files/topotekafuwokaremo.pdfIn PDF document text
    • http://esteel.my/userfiles/file/kexatep.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614607c2b1b60---kusamitizi.pdfIn PDF document text
    • http://synhbio.com/upload/files/guzorisosemaji.pdfIn PDF document text
    • http://cerrutistudio.eu/userfiles/files/fudes.pdfIn PDF document text
    • https://sapthagireesyathra.com/userfiles/file/27912737287.pdfIn PDF document text
    • http://thsport.dk/userfiles/file/46753629028.pdfIn PDF document text
    • https://lwim-ouargla.dz/ar/files/73657562219.pdfIn PDF document text
    • http://wsystem.sk/userfiles/files/36210593227.pdfIn PDF document text
    • https://ontogepszerviz.hu/editor_up/lijatezibusopivem.pdfIn PDF document text
    • http://gardensyellowcab.com/admin/images/file/gogokuzugilovalutojox.pdfIn PDF document text
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/b59129bb2c388feb61ea42ea507803ee/dowasedate.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/16156058bc6828---12546946551.pdfIn PDF document text
    • http://gcsiva.com/files/userfiles/file/51635137188.pdfIn PDF document text
    • https://sofupingame.net/calisma2/files/uploads/57845512732.pdfIn PDF document text
    • http://jacsonsfurniture.com/userfiles/file/46304862114.pdfIn PDF document text
    • http://pbhdom.eu/userfiles/file/lenuva.pdfIn PDF document text
    • http://alessandrotria.altervista.org/areap/ckfinder/userfiles/files/vudujosufopuxazoletizupex.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://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_off0000b1ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1EC 17188 bytes
SHA-256: e0fdfde1e177cbdcb587fb27491884ba51c52d781277e8f0abe79705541b525d
font_01_sfnt_off0000de2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE2B 10420 bytes
SHA-256: 9aa3f3090747d080ffaa0ef72eb1e38c96f5a583dcc98e599ccdb135e0c43f13
font_02_sfnt_off0000f5c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1