Malicious PDF — malware analysis report

Static analysis result for SHA-256 777fbc86ba1b10d5…

MALICIOUS

PDF

124.7 KB Created: 2021-08-01 00:23:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: b8d1b33262a2b92bbf494c12861e7795 SHA-1: 1dde994f40731239245bbc2e5f21370f6e626f7e SHA-256: 777fbc86ba1b10d514e6fb44e2a606ba29d6bcb9b18ecf4f9d4ad436ec6b58f3
156 Risk Score

Malware Insights

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

This PDF was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV detecting it as a phishing trojan. It contains numerous external links, many pointing to compromised WordPress sites, suggesting it's part of a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, indicating an attempt to hide its true purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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://oniceh.ru/uplcv?utm_term=que+se+entiende+por+modo+de+produccion+esclavista PDF link annotation
    • http://samurairamenbar.com/uploads/files/28087415652.pdfIn PDF document text
    • http://logtech.cz/foto/Image/file/50352257752.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b0c5e5df997---61928459915.pdfIn PDF document text
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/7d763c242585ebbf926ee5fdb9fe6a8c/22832269937.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f39b1bae08---23088499419.pdfIn PDF document text
    • https://prosegik.com/wp-content/plugins/super-forms/uploads/php/files/d17261aa9f5b30347c14cbb2be5ba940/nipagivusutol.pdfIn PDF document text
    • http://php-lounge.de/userfiles/file/wedajelonorimixe.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acf31f44be0---96771163977.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/qjjvggq3nt5ohd851np24gu0uh/81450468098.pdfIn PDF document text
    • http://faizleathergloves.com/userfiles/files/65543661540.pdfIn PDF document text
    • http://sunnysideclassof64.com/clients/a/ac/acc4ccb49d7935ca36198347b895393e/File/gejetamazuja.pdfIn PDF document text
    • http://fobosgrunt.ru/files/ckfinder/files/fulivobodif.pdfIn PDF document text
    • https://europartner2.pl/uploads/12544010368.pdfIn PDF document text
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/5daaecc441dca9568a747dccd1b01107/dozuzo.pdfIn PDF document text
    • http://artpolinakuzina.ru/pict/file/jemosonavosobav.pdfIn PDF document text
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/03rbtpar9d2l0quvaad3b23d36/73560095992.pdfIn PDF document text
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/160728e9e530d1---98648526628.pdfIn PDF document text
    • https://mkting.com.co/wp-content/plugins/super-forms/uploads/php/files/2bc8e0fedc3662590f16448d4364229a/98727903822.pdfIn PDF document text
    • https://yziact.fr/wp-content/plugins/super-forms/uploads/php/files/nu45rec1h1ferdhjo6irla8r81/guwibopado.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a0746aad163---95036726844.pdfIn PDF document text
    • http://www.onlinetemsilci.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ecd9f341c7---memaxanamenib.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608655790a479---tawugotalujazubuzazulid.pdfIn PDF document text
    • https://i3mit.com/shopadmin/upload/files/tutumakefumetavudovowe.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a3de863d67---balajadebixufefoliwapu.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16089753cdf2a6---16144308948.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_off00017ed9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17ED9 21160 bytes
SHA-256: 61aec5822fba5350765dce5b887eaf2ce7d09afa0b90400b780c7919867cfdaf
font_01_sfnt_off0001b318.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1B318 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001cb2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1CB2F 10900 bytes
SHA-256: 154d82bdd9aa694f7ede2f9b5e2dad83a043f2108b62e1010bb76a3b3c209c16