Malicious PDF — malware analysis report

Static analysis result for SHA-256 c7fffc3fe20d5389…

MALICIOUS

PDF

81.3 KB Created: 2021-09-11 22:25:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: f9a540592b89c753b78347b5bbabbf63 SHA-1: 049aff0b25a5faacfa7816132bf0f74b4242d1c9 SHA-256: c7fffc3fe20d5389f3d28e9fd492fe930b18e98cc2338c2fb34f9654e41872e3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and links to other PDF files hosted on various domains, many of which appear to be compromised or disposable. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond what the heuristics reveal.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://crysiq.ru/uplcv?utm_term=application+manager+android PDF link annotation
    • https://emartdeko.pl/galeria/file/73917443561.pdfIn PDF document text
    • http://rayocazar.com/images/elfinder-1.1/files/file/85792641211.pdfIn PDF document text
    • http://thietbikhachsanvinhhung1.com/upload/files/mivopunomofajevixixisuro.pdfIn PDF document text
    • https://fengshan-zhennangong.org/upload/ckfinder/files/63996254213.pdfIn PDF document text
    • http://rutka.pl/media/upload/files/8fa719f36d733fba122355e1f6aaa7b8.pdfIn PDF document text
    • http://budropol.de/Upload/file/kisube.pdfIn PDF document text
    • http://kiapelhrimov.cz/UserFiles/File/89212950883.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16138374784af1---safabizew.pdfIn PDF document text
    • http://fxlcd.com/upload/file/nifeva.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161388e4eedb12---53315199860.pdfIn PDF document text
    • http://sahcarpets.com/userfiles/file/83093873284.pdfIn PDF document text
    • http://akademibt.com/resimler/files/xenuxevu.pdfIn PDF document text
    • http://champaigncursillo.com/userfiles/file/xagimojeguwidilusalaz.pdfIn PDF document text
    • http://lovesenergy.nl/file/toxamopa.pdfIn PDF document text
    • http://konditsionery-odincovo.ru/upload_picture/file/87675284566.pdfIn PDF document text
    • http://storemisr.com/uploads/files/57178870051.pdfIn PDF document text
    • http://refinerlink.com/userfiles/file/73072901678.pdfIn PDF document text
    • http://food-cloud.com/home/food-cloud/www/site/site/data/files/51165159003.pdfIn PDF document text
    • https://rmdschoolandcollege.com/wp-content/plugins/super-forms/uploads/php/files/8ef5e5e319d4fd3fda69e81d4c4ee772/89347192757.pdfIn PDF document text
    • https://rwd.webseo.tw/upload/files/buwiguxosuk.pdfIn PDF document text
    • https://tutorbolivia.com/userfiles/file/39835324811.pdfIn PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/e1788305d0ae98a359cd816adf9afed0/1065902000.pdfIn PDF document text
    • http://ceramicaartisticamarsalese.it/userfiles/files/ridojez.pdfIn PDF document text
    • http://toyotaquangninh.org/data/dulieu/files/30650246417.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_off0000d7d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7D7 18128 bytes
SHA-256: 733b5dd908b54b82b91ee48254cbb57a2254ad91688315e999ed0aa439db2510
font_01_sfnt_off000106d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106D7 10672 bytes
SHA-256: a09a4a1d0140abd6c1fef75f13d0a363b4c1235ce23fa6119f799479b06a9d31
font_02_sfnt_off00011f19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F19 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1