Malicious PDF — malware analysis report

Static analysis result for SHA-256 171cefc559ea415f…

MALICIOUS

PDF

82.1 KB Created: 2021-09-15 15:33:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 27eaa7769c7a4283edddb230cd8aac27 SHA-1: ade03b6880a49edf902754e8aa82fb70d16954f7 SHA-256: 171cefc559ea415fdab1dc57526f132bec207b20fdea75c6bd9968c28951fbc2
164 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to external sites, some of which are hosted on compromised CMS platforms or disposable domains. These links likely serve to lure users into downloading further malware or engaging in phishing activities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://pixomot.ru/uplcv?utm_term=undead+slayer+mod+apk+offline+free+download PDF link annotation
    • http://eternalcycle.com/FCKFiles/file/dugofateruvusowinibomufo.pdfIn PDF document text
    • http://fuzoku-kyujin.jp/ckfinder/userfiles/files/90861285086.pdfIn PDF document text
    • https://xn--espaoldetalca-lkb.cl/var/www/html/upload/file/8571620027.pdfIn PDF document text
    • http://ruihuitax.com/files/file/419208585.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161416d901ee6b---558732376.pdfIn PDF document text
    • http://grupopiscis.com/upload/files/33270635183.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/73c543eaa9a70d08ab1f479848153bb1/pogalasat.pdfIn PDF document text
    • http://levotst.com/uploads/files/negamekif.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f9884b57f6---6046413240.pdfIn PDF document text
    • https://preprodpcb.com/userfiles/files/62775297445.pdfIn PDF document text
    • http://yourmoneyyourbank.com/uploads/File/72104055582.pdfIn PDF document text
    • http://pes.edu.mn/ckfinder/userfiles/files/tigogumariwilinejig.pdfIn PDF document text
    • http://pizzeriadevita.it/userfiles/files/nogoxalebu.pdfIn PDF document text
    • http://ngocvietbungalow.com/upload/files/85306418220.pdfIn PDF document text
    • http://szhlfz.net/upload/5975908445.pdfIn PDF document text
    • http://vivaldiskibus.com/FileData/ckfinder/files/20210915_F7FB9B218981E6B1.pdfIn PDF document text
    • https://iwanbim.iwan.co/userfiles/files/xajewaresazuti.pdfIn PDF document text
    • http://xn--80aikni6a0b.xn--p1ai/images/file/14194243471.pdfIn PDF document text
    • http://uat2.hkha.com.hk/ckfinder/userfiles/files/46150745221.pdfIn PDF document text
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/75007cf63ddd251ce8931cadba0e8d44/bivilokosarijetijato.pdfIn PDF document text
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614147ed67a34---wufamireworirufosam.pdfIn PDF document text
    • http://protetyka-lublin.com/images/wyswig_images/file/negezapifamidusudiraser.pdfIn PDF document text
    • https://eyetracking.pl/userfiles/file/nagomaxasegebewofosoti.pdfIn PDF document text
    • http://kondicionery-noginsk.ru/upload_picture/file/toratexivomeviravisewa.pdfIn PDF document text
    • http://mansiya.com/uploadfile/files/14295005206.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_off0000db55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB55 17624 bytes
SHA-256: 8cc8f0c00d6be4bbb3d647fc404ed9c75ea191736f33544ad5214ceeae9862c1
font_01_sfnt_off000108de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108DE 10860 bytes
SHA-256: 1c0b248c87c224ee966f4802da2c71560d11a49b2da91862dbdfd76f618918d0
font_02_sfnt_off000121fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121FA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1