Malicious PDF — malware analysis report

Static analysis result for SHA-256 f1cb1e1a50abae4a…

MALICIOUS

PDF

83.4 KB Created: 2021-09-23 11:25:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: ce491f3b22e114b1de9ce58fbef4e3d5 SHA-1: 1a0584bd65dbc352df94e1d0adfb313a6776f509 SHA-256: f1cb1e1a50abae4a1dd9fdc4ab4075fd5f874208ba789f6c16fb46810fe745af
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm. It contains numerous URLs pointing to potentially compromised websites and disposable hosting, suggesting an attempt to distribute malicious content or phish users. The presence of external URI links and compromised CMS upload links indicates a redirection mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • 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.
  • 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=herramientas+para+crear+aplicaciones+android PDF link annotation
    • https://cryptobasics.biz/uploads/files/jubuxawogezegabitisuvolij.pdfIn PDF document text
    • http://studiomalpocher.it/userfiles/files/tivoruloguvefo.pdfIn PDF document text
    • http://baovethanglongmb.com/upload/files/kodixukomuta.pdfIn PDF document text
    • http://apex-architect.ru/images/file/9521645747.pdfIn PDF document text
    • https://agriplan-rs.com/dados/ckfinder/files/32587716542.pdfIn PDF document text
    • http://cimkezes.hu/uploads/ckfinder/userfiles/files/48011031690.pdfIn PDF document text
    • http://biomehl.com/images/content/files/mubovaxusedogomo.pdfIn PDF document text
    • http://les-dvorik.ru/userfiles/file/jejopinudavusaferowes.pdfIn PDF document text
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/bf4d18174f603f9573dd29500c47cafa/37314205699.pdfIn PDF document text
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/7b62cfc313e30d65448a0fc8593b91db/xapigokiluki.pdfIn PDF document text
    • https://goodline.by/userfiles/file/delupe.pdfIn PDF document text
    • https://magnettoptan.com/upload/ckfinder/files/46664854005.pdfIn PDF document text
    • https://lufty.cz/UserFiles/files/56919135277.pdfIn PDF document text
    • https://centrorevisionimonregalese.it/file/50280064750.pdfIn PDF document text
    • https://alusol-kw.com/ckfinder/userfiles/files/pewexitujobimam.pdfIn PDF document text
    • http://www.examnotice.in/uploads/files/pibosumowolibu.pdfIn PDF document text
    • https://rkdestate.com/userfiles/file/69541164292.pdfIn PDF document text
    • http://ildungrice.com/fileupload/fckeditor/file/nugegegapevemegumi.pdfIn PDF document text
    • http://dentistturkey.com/image/files/nuwebizixa.pdfIn PDF document text
    • http://www.moyekolodin.com/files/zaregukowopeg.pdfIn PDF document text
    • https://begili.com/uploads/image/files/zibutomuwilirejepopejodiw.pdfIn PDF document text
    • http://starfishdowney.com/uploads/files/gituzafuberuxaguwazetodi.pdfIn PDF document text
    • http://bjhtdszdh.com/v15/Upload/file/2021921835547222.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/161325bf44ef09---sugebijoreragalu.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_off0000e06d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE06D 17888 bytes
SHA-256: 505531f30c99e689673b9a44225902edd0aab480c21ec727ad49369d0ae60a97
font_01_sfnt_off00010da2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DA2 10668 bytes
SHA-256: ac48ed40f2b903bf09d051350bee26d2c2642d7ff773c8c8043144e3e47f05bf
font_02_sfnt_off000125fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125FB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1