Malicious PDF — malware analysis report

Static analysis result for SHA-256 640d840141655406…

MALICIOUS

PDF

71.2 KB Created: 2021-10-02 10:16:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c43af179fc5ffa6c7e8ef14d4ce76f8c SHA-1: b60855255575b155498520a2e585a9346a6eb391 SHA-256: 640d840141655406f20b7eae385ca59de4c9c06567285bca9dd3b98976363525
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF file contains numerous external links, many pointing to compromised or disposable domains, suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the nature of the link farm and the PDF format itself often leverage embedded JavaScript for malicious redirection or exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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://imbirimbir.ru/files/zomulop.pdf
    • http://azseal.net/uploads/userfiles/file/tevetasesonisabi.pdf
    • http://naviway.su/upload/files/94637785188.pdf
    • https://elitteaccesorios.com/wp-content/plugins/super-forms/uploads/php/files/mjin7e1t9r4tkdghkkm15r695h/dulekuti.pdf
    • http://labradory.pl/file/89275736648.pdf
    • http://artpolinakuzina.ru/pict/file/faxofisatefotebopenojimob.pdf
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1614f9d2655740---74570060767.pdf
    • https://buyafranchise.org/files/files/jajaborilubosigupifix.pdf
    • https://maintogelonline.bet/contents/files/99597305842.pdf
    • https://cnprint.ro/userfiles/file/99931069175.pdf
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/e0fc214eo5nf2fbtrb5nrihmeg/zizafaleruxexix.pdf
    • https://siam-royal-view.ru/data/files/11982917389.pdf
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/1613f10fb1becb---47738957154.pdf
    • https://sowlindia.com/userfiles/file/newiwaleg.pdf
    • https://spyboarcams.com/files/13941988469.pdf
    • http://cssh.es/img/file/ruwowemezejo.pdf
    • https://aawyx.com/sites/default/imageuser/file/15094939463.pdf
    • https://divorcioconsensual.com.br/wp-content/plugins/super-forms/uploads/php/files/060bb8176a085cff9557c9c0b3890aff/majudowofusasupu.pdf
    • http://kocavietnam.com/upload/files/17322897066.pdf
    • http://stefanourso.com/public/userfiles/file/50286662324.pdf
    • https://www.aledrukujemy.pl/ckfinder/userfiles/files/rasasodiduwiravibewulep.pdf
    • https://znalac.com/userfiles/file/nezigokebafizezozikov.pdf
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1614b49bc73d51---26709851525.pdf
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cb0c388576---disatudalu.pdf
    • https://dolupin.com/calisma2/files/uploads/mijuzosonot.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=html+permanent+redirect
    • http://pro.ovh.net/~tribuene/images/banque/file/xibobirasugaralefugifil.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_off0000b5f0.bin
92ab4ba55d5fefc20a400a11fbf9f9a0150db552982121801e2d67f2f00dc2e7
pdf-font-stream PDF embedded font (sfnt) at offset 0xB5F0 16448 bytes
font_01_sfnt_off0000dfbf.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDFBF 16792 bytes
font_02_sfnt_off0000f7d6.bin
d2a9f6bb59ab673ab654af4c8c85e68e6224ec2d98d24be8b2f6d7f08faaa314
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7D6 10380 bytes