Malicious PDF — malware analysis report

Static analysis result for SHA-256 b248f74b08e479e2…

MALICIOUS

PDF

75.8 KB Created: 2021-09-08 05:28:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c62de062b3d07c29db86b50fad40e62e SHA-1: 144cb5f33074bf149adfa20a6d7e7acc1fdcf842 SHA-256: b248f74b08e479e205b525b7569a9f01e15aceeea0ffd2dc97a58af5a1aeeb4f
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier. Heuristics indicate it functions as a link farm, with multiple URLs pointing to compromised CMS upload storage and disposable hosting. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather to host links. The presence of numerous unknown URLs strongly suggests an attempt to redirect users to malicious sites for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://zoncmswebsitebeheer.nl/files/editor/file/lidirupona.pdf
    • http://mnwebdesign.dk/userfiles/file/13308644388.pdf
    • https://southernlightingsource.com/wp-content/plugins/super-forms/uploads/php/files/51925dff26892dbe640c9ee3c1874de6/47889265145.pdf
    • http://hydrogears.com/survey/userfiles/files/fixodebobelezidurojot.pdf
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16086978dd4f2a---wiravabiruguposuxetetivo.pdf
    • http://geologocarmignani.com/userfiles/files/jidirezetajabivajomexak.pdf
    • https://www.businesswatchguardingservices.co.uk/wp-content/plugins/super-forms/uploads/php/files/p9j5av4n0rco40a33iphhkp1i6/wurunovoxe.pdf
    • http://tutaylamhet.com/storage/ckfinder/files/84439245854.pdf
    • https://mertlakustika.cz/images/pages/file/31145972413.pdf
    • https://kicksomeglass.com/wp-content/plugins/super-forms/uploads/php/files/f316b98d84f5dd5e85c56f8bbace1b91/jinelitiremonelika.pdf
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b40af613504---34773129568.pdf
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078557601531---61578315859.pdf
    • http://stonebreaker.at/17166524654.pdf
    • https://carstenrath.com/wp-content/plugins/super-forms/uploads/php/files/jpp5pnefjigol9m118ekf659f4/kojowekidaxibapuzo.pdf
    • https://accesoriosalmayor.com/images/userfiles/file/sibasakixusajofoxajironut.pdf
    • http://projectbudapest.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1607622efc0f49---42118189113.pdf
    • http://hotararicedo.ro/files/files/34787149333.pdf
    • http://zhuoer.ltd/userfiles/file/jekegirenesigikupuval.pdf
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bef0852dd4---molifokurorizulasirenoro.pdf
    • http://thankschicken.com/uploads/files/dolakode.pdf
    • http://nuestratierrapremios.com/campannas/file/novubukubowo.pdf
    • http://al-bandak.com/userfiles/file/3614037781.pdf
    • https://t2sc.me/userfiles/jetutesuzofavazojajemefam.pdf
    • http://danburyhighclassof1961.com/clients/b/b4/b42d7d7907ff1a67dd6fd366dd3c6775/File/gidisibipazerepukirewev.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=cambridge+dictionary+book+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000be37.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xBE37 16792 bytes
font_01_sfnt_off0000d649.bin
c5b8d5b9f1c6b35288d7ae9f6f616008fa9e3662247d6d543f275970bcce8a7f
pdf-font-stream PDF embedded font (sfnt) at offset 0xD649 19200 bytes
font_02_sfnt_off00010808.bin
7e94a2fecb78332ff343dbba4e372af2c73cd2daf18343abf04e04c41353db50
pdf-font-stream PDF embedded font (sfnt) at offset 0x10808 11124 bytes