Malicious PDF — malware analysis report

Static analysis result for SHA-256 def902261fb688fe…

MALICIOUS

PDF

79.2 KB Created: 2021-09-05 16:29:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: aa4d4136d575145ac972f295f51801bb SHA-1: 8a22bf19bf6ae26027abde1c66d27559b1c7f7fa SHA-256: def902261fb688fe77d80af217289e1427fa55c0bc156d2fa2f63f75457c3667
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicative of a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated and unreadable, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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 http://budka39.ru/files/kizagibutajopolofo.pdf In PDF document text
    • http://personnelstrategies.net/userfiles/file/lirizupupazewowova.pdfIn PDF document text
    • http://sevoir.hu/uploads/file/22067385277.pdfIn PDF document text
    • http://edgecs.net/documents/15120588773.pdfIn PDF document text
    • https://nguoixunghekiev.vn/userfiles/file/46511256360.pdfIn PDF document text
    • http://nordicaluminium.ru/userfiles/file/13964354929.pdfIn PDF document text
    • https://peilimineko.com/userfiles/file/2338169132.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f9d18ee4b8---kivowinadepagijazorelava.pdfIn PDF document text
    • http://koovappadyscb.com/ckfinder/userfiles/files/tazarokimomewujut.pdfIn PDF document text
    • http://fskyok.com/uploadfile/files/pajufobafovedozoxamojeket.pdfIn PDF document text
    • http://teresachild.com/upload/files/tewixadotuku.pdfIn PDF document text
    • http://zaun-produzent.de/userfiles/file/rifiwadijapekopal.pdfIn PDF document text
    • https://vinniescustoms.com/userfiles/files/loninetizukorekobal.pdfIn PDF document text
    • http://dobryremont.pl/ebobas/portal/app/webroot/img/tmp/file/16208004185361.pdfIn PDF document text
    • https://pcparts.fr/ckfinder/userfiles/files/79659208427.pdfIn PDF document text
    • https://vico-domrep.com/ckfinder/userfiles/files/sadisazimepow.pdfIn PDF document text
    • http://elijasprojekts.lv/files/file/84744310377.pdfIn PDF document text
    • https://gservicepz.com/wp-content/plugins/super-forms/uploads/php/files/132ae4f388f42be23adb921d807ec3ec/47083055437.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa77ff28ae5---79313564631.pdfIn PDF document text
    • https://twr1115.net/files/fckeditor/file/kowemesi.pdfIn PDF document text
    • http://bellina.pl/userfiles/file/wirunuso.pdfIn PDF document text
    • http://dexgerm.com/data/file/userfiles/files/kijuporokotutedurazo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=pdf+pages+merge+into+one+pagePDF 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_off0000d192.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD192 10796 bytes
SHA-256: abf5bb40de05d1cd0651de882fdebcb0c7a01e00147d8eeb643ff4efa092a093
font_01_sfnt_off0000ea3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA3C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001024e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1024E 17648 bytes
SHA-256: acd26117be8638ecc7c4c0af5927f9adde0860840222ca2989a9ab851175730d