Malicious PDF — malware analysis report

Static analysis result for SHA-256 319681d833cbda8b…

MALICIOUS

PDF

84.2 KB Created: 2021-08-04 01:58:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 38036ddda75ce9ecde5515ab2317761a SHA-1: d4495144300bc5cb8a63cfba6b582d5126bf13bb SHA-256: 319681d833cbda8b2e2399b920fd55135461e25ed22e2b723ae1d9d69c58ccdc
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that point to compromised websites, indicating a link farm designed to redirect users to malicious content. Heuristics suggest this is a phishing or malware distribution attempt, with ClamAV specifically identifying it as 'Pdf.Phishing.Trojan'. The ML classifier also strongly flagged the PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://nomylo.ru/uplcv?utm_term=how+to+fix+hamilton+beach+flexbrew PDF link annotation
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/3bd535cbf20a59a1dbb19bf796c171a5/3660007599.pdfIn PDF document text
    • https://chokysitohang.com/Uploads/userfiles/files/xezagiranemaxejiwuzigob.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160906195dbd58---lusibapixur.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/1610658bec8c59---nategifalabu.pdfIn PDF document text
    • http://innotack.com/userfiles/files/5797211764.pdfIn PDF document text
    • http://blpest.com/UserFiles/file/85798531527.pdfIn PDF document text
    • http://memsports.com.br/admin/libs/ckeditor/ckfinder/files/tuloxetobaxesewifiwid.pdfIn PDF document text
    • http://stroisvias.ru/userfiles/file/julub.pdfIn PDF document text
    • https://podimercrm.com/img/files/46262585551.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160851ff34f501---61393710211.pdfIn PDF document text
    • http://orbitsecurity.qa/pro_mvp_tech/uploads/file/65158448902.pdfIn PDF document text
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/160abd7e800438---81711019411.pdfIn PDF document text
    • https://rcvizovice.cz/ckfinder/userfiles/files/ruvugulawi.pdfIn PDF document text
    • http://lsneotek.com/ckupload/files/geligetino.pdfIn PDF document text
    • https://promise-land.com/upload/file/telonetulenobem.pdfIn PDF document text
    • https://willmarareachamber.com/ckfinder/userfiles/files/xafeg.pdfIn PDF document text
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/5fafb6445eb21a279fb594f514cd88de/93157780966.pdfIn PDF document text
    • http://banglenhospital.com/UserFiles/File/vejatajodebozajuz.pdfIn PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/pv7h0sd4hput44e8fhv61gklq2/27336727264.pdfIn PDF document text
    • http://resortvillairene.it/userfiles/files/67479601419.pdfIn PDF document text
    • https://rsun.pro/admin/ckfinder/userfiles/files/56081629903.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_off0000e785.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE785 16656 bytes
SHA-256: b7f0da444b125d835eb867d7306a0792bc5b9184950d90a9a5971242437ea3cb
font_01_sfnt_off00011292.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11292 10752 bytes
SHA-256: 6dbe5525027f48c89c95b8d119740499399691ecd7f8ef4df59174c3ca501ded
font_02_sfnt_off00012b1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B1D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1