Malicious PDF — malware analysis report

Static analysis result for SHA-256 36b0688ed9370ab3…

MALICIOUS

PDF

69.8 KB Created: 2021-10-06 02:13:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 07dec0b61bbb9a21159afd912771fea0 SHA-1: ed0fe5c93e20864ab62667851d2e5260b52b47b5 SHA-256: 36b0688ed9370ab3b843ed87da721ffa6f5a944873dae700a07d297dc892d43c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a phishing lure disguised as job interview preparation material.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://crysiq.ru/uplcv?utm_term=it+support+job+interview+questions+and+answers PDF link annotation
    • http://aeronautike.com/userfiles/file/87351482603.pdfIn PDF document text
    • http://cascinamana.it/userfiles/file/25273740716.pdfIn PDF document text
    • https://hacunamatata.ru/wp-content/plugins/super-forms/uploads/php/files/e9d412496a1beb6927058af64e8b59ec/35295899389.pdfIn PDF document text
    • http://ruben.pl/ckfinder/userfiles/files/28589990842.pdfIn PDF document text
    • https://siangyun.com/upfiles/editor/files/mijipijapupevikomagafe.pdfIn PDF document text
    • https://www.highlandernepal.com/assets/ckfinder/userfiles/files/33010221455.pdfIn PDF document text
    • http://self119.net/upload/userfiles/2021/09/files/210902192143.pdfIn PDF document text
    • http://sgadsahodayatarntaran.org/sahodyatarntarannew/userfiles/file/teduguviwesuj.pdfIn PDF document text
    • http://bugaboo-buffalo.eu/UserFiles/File/vizogud.pdfIn PDF document text
    • http://samurairamenbar.com/uploads/files/27009504505.pdfIn PDF document text
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16155e033b5cb3---57673321961.pdfIn PDF document text
    • http://2222.netsociality.com/upload/files/9776634568.pdfIn PDF document text
    • http://waycreon.net/bhaskar/yii/upload/files/nudosuxofufijofu.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138792691142---52740322789.pdfIn PDF document text
    • https://hiperaktivite.info/userfiles/files/15511682140.pdfIn PDF document text
    • https://sibservis.com/ckfinder/userfiles/files/wozaxuxawip.pdfIn PDF document text
    • http://f-okinawa.com/img/tmp/files/53844132940.pdfIn PDF document text
    • http://trumoi-khutrung.com/upload/files/35815960199.pdfIn PDF document text
    • http://ever0036.com/assets/uploads/ckedit/files/20211006070832.pdfIn PDF document text
    • http://4x4autok.hu/userfiles/files/fonadesaxisavixu.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_off0000b076.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB076 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c88d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC88D 10956 bytes
SHA-256: a97ef97bd95b901fb4a392a80f12b29cfd380a332e239d7e147987c146a2fc32
font_02_sfnt_off0000e1a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1A9 15988 bytes
SHA-256: 0d53be22e47a6679d5e8ccfc092eba830f5810c77afb23ec87c7410bc182c178