Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb31a05e9b47face…

MALICIOUS

PDF

79.1 KB Created: 2021-09-18 21:17:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: a543109b5ae2b80b2faf3690c472346c SHA-1: 2af1224cbf0f1cedcb47abec795574b9b630dede SHA-256: bb31a05e9b47face34a6b2850dfeb23687aa6f6697d86a9bc3da896156c1e69a
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be compromised CMS upload directories or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. The presence of multiple link farms suggests an attempt to obscure the ultimate destination or to distribute malicious content across various compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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://infrive.ru/uplcv?utm_term=best+text+on+photo+app+android+2020 PDF link annotation
    • http://semanbio.com/upload/files/sibajovifananuxipuba.pdfIn PDF document text
    • http://tweedehandswikkelaar.nl/app/webroot/files/userfiles/files/33759149499.pdfIn PDF document text
    • http://geodavidepini.it/userfiles/files/gipadelijuxugefumukazubef.pdfIn PDF document text
    • http://vervesimuhub.com/userfiles/file/4888639205.pdfIn PDF document text
    • http://osteriadelcampanile.com/userfiles/files/51545384047.pdfIn PDF document text
    • https://norservis.com/files/files/60473644527.pdfIn PDF document text
    • https://suacuachuyennghiep.com/uploads/files/pijuf.pdfIn PDF document text
    • http://telegid.tv/userfiles/file/dajofuludowerunap.pdfIn PDF document text
    • http://canadanur.com/resimler/files/53414209228.pdfIn PDF document text
    • http://abwingsbuffalo.com/uploads/files/24889096217.pdfIn PDF document text
    • https://cardolf.ro/files/89741081785.pdfIn PDF document text
    • http://hoya-system.com/uploads/files/202109020337477443.pdfIn PDF document text
    • http://zhizhencn.com/filespath/files/20210904043433.pdfIn PDF document text
    • http://warwick-ems.org/userfiles/file/zatamobigulub.pdfIn PDF document text
    • http://shesob.com/file/files/36682255728.pdfIn PDF document text
    • https://media-get.ru/userfiles/files/51098906401.pdfIn PDF document text
    • https://sreekanakananda.com/ckfinder/userfiles/files/neluwizepufarobuxegugeko.pdfIn PDF document text
    • http://ihdbd.org/upload/files/neniwelibanadudapiwunubo.pdfIn PDF document text
    • https://cambodiadriverservice.com/userfiles/file/redokemalozudu.pdfIn PDF document text
    • https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/16a87ca13bf83355b50ce91d597f5efd/rubitabalesepesisosoligez.pdfIn PDF document text
    • http://medical-1669.com/userfiles/files/wavanejimetusokafodi.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613e3040ed6cc---puvevidum.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161401920b4fc1---tutajokekevipitubofusaw.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_off0000d1f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1F5 10840 bytes
SHA-256: 25ad928524b041c2a9652de2d91de9c9a92b97be178978c6d94bae4a9541f2c3
font_01_sfnt_off0000eafd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAFD 17244 bytes
SHA-256: ecad7a4bd73c46f533970d5a0405922f299a8f5ed319550b9c28930acc920a1b
font_02_sfnt_off000116f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116F0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1