Malicious PDF — malware analysis report

Static analysis result for SHA-256 39b308991197e7fc…

MALICIOUS

PDF

85.0 KB Created: 2021-09-16 15:55:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 56b90628c057ed13e5be4a5dd9b5d149 SHA-1: 2ac9adae714b3649b5bc9cb5281068fb371c8808 SHA-256: 39b308991197e7fce91bb9f2357708ccde2db6c0368d53e40b369e03a1afbb00
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://crewmak.ru/uplcv?utm_term=city+games+for+android PDF link annotation
    • http://hitecds.com/userfiles/file/kavutupepolimejov.pdfIn PDF document text
    • https://camgloberealtor.com/userfiles/file/jejoduvujazafum.pdfIn PDF document text
    • http://okmarin.ru/userfiles/file/97249430185.pdfIn PDF document text
    • http://felixefontesadvogados.com.br/ckfinder/userfiles/files/84520789587.pdfIn PDF document text
    • https://perfectprojects.ro/userfiles/file/62005523840.pdfIn PDF document text
    • https://lawweb.info/mycms/admin/userfiles/file/53610637317.pdfIn PDF document text
    • https://stomatoloska-ordinacija-rijeka.com/files/50186620901.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/bp527pggvlvsnpu896tlc5g2ae/dasojexitaxitebeb.pdfIn PDF document text
    • https://askisan.com/upload/ckfinder/files/33982945339.pdfIn PDF document text
    • http://adwokaci-pila.pl/userfiles/file/wifipuwibodasuwirimozoba.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/161366499ca2f6---vifof.pdfIn PDF document text
    • http://bhk-aindling.com/userfiles/files/87666800777.pdfIn PDF document text
    • http://aygroupmuh.com/image/files/lamakabujopesubise.pdfIn PDF document text
    • http://buren-kompanie.de/userfiles/files/nawisukovata.pdfIn PDF document text
    • http://travel-door.com/userfiles/file/ligatejilosorudesizito.pdfIn PDF document text
    • http://tanabuauto.com/js/upload/files/sekupaduvamalewaxaluwofi.pdfIn PDF document text
    • http://longruiglass.com/ckfinder/userfiles/files/20210914_170259.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/0ca396a54b461d1fae982e0f5f19cb98/sesiremexujepipoma.pdfIn PDF document text
    • https://demideopool.ro/ckfinder/userfiles/files/mevaso.pdfIn PDF document text
    • https://radmangroup-ye.com/rgfiles/file/83442008448.pdfIn PDF document text
    • https://onsale.social-push.cc/data/fckeditor/files/37301618135.pdfIn PDF document text
    • http://xn--80adpfaaeictf0c6c7i.xn--p1ai/public/file/wakefizenedosesagoduw.pdfIn PDF document text
    • https://stmpallet.com/ckfinder/userfiles/files/98040749041.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_off0000e9aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9AA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000101c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101C1 10796 bytes
SHA-256: 7fe506efed6517e997ce73898ad630a331c0e819cec31f03941da206119e0887
font_02_sfnt_off00011a7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A7D 17332 bytes
SHA-256: 0a2a7ccd2d13a51260cfb264409632a72992993b66d8d7679c140e430cd6575f