Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc6c5b7eac0c7c63…

MALICIOUS

PDF

86.1 KB Created: 2021-09-20 14:19:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 53a102343e657ed5e25b1d235b65e307 SHA-1: 3120931e3b7b35986970ccb672c2134c4fb44538 SHA-256: bc6c5b7eac0c7c63effe5ea671275217959364280db4a264d2a26bb4a2b7d4e9
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. Multiple heuristics indicate the PDF contains numerous external links, some pointing to compromised WordPress upload storage and disposable hosting, suggesting an attempt to distribute malicious content or phish users. The presence of embedded URLs and the overall structure strongly suggest a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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=android+commander+alternative PDF link annotation
    • http://mistral-paints.cz/userfiles/files/pakix.pdfIn PDF document text
    • http://studiobaldizzone.com/userfiles/files/wifutiduzisojifokavefumo.pdfIn PDF document text
    • http://gibkrakow.pl/uploads/files/faxinatijaxuxu.pdfIn PDF document text
    • http://directopinion.biz/uploads/FCK_files/file/jekobesifavomamad.pdfIn PDF document text
    • http://rszm88.com/upfolder/e/files/20210920095129.pdfIn PDF document text
    • http://z-him.ru/userfiles/file/82198178058.pdfIn PDF document text
    • http://massimosusto.eu/userfiles/files/lumojugamenufevumobu.pdfIn PDF document text
    • http://ourgans.org/userfiles/files/33368735323.pdfIn PDF document text
    • https://khambenhxahoi115.com/images/files/8514700447.pdfIn PDF document text
    • http://studiopignotti.it/userfiles/files/74834201541.pdfIn PDF document text
    • http://old.smartplus.pl/ckfinder/userfiles/files/11930133853.pdfIn PDF document text
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fbc84e1821---wesubozuwoledudadore.pdfIn PDF document text
    • http://a2hgghk.handylover.com/upload/files/lerotakivonaz.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/161413b527b92d---gezasilet.pdfIn PDF document text
    • https://client-sms.com/ckfinder/userfiles/files/2461889307.pdfIn PDF document text
    • http://tzoetemondje.be/uploads/files/donamumoja.pdfIn PDF document text
    • http://orthodoxnews.us/file/20351201800.pdfIn PDF document text
    • https://tenfci.org/userfiles/file/69852189694.pdfIn PDF document text
    • http://nguyenxuanhuong.com/upload/files/tebokasizukipiwodo.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/1613d87e2a9911---goxenuzobeja.pdfIn PDF document text
    • https://accidentmatters.com/ckfinder/userfiles/files/23318977344.pdfIn PDF document text
    • http://erodiertechnik-wenzel.de/userfiles/file/1773380703.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/161307a5ec34dc---69496671092.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/161429e300b3ee---dexotofesukeb.pdfIn PDF document text
    • http://erbamedica.org/userfiles/files/posoduvufi.pdfIn PDF document text
    • http://speednewslive24.com/assets/ckfinder/core/connector/php/uploads/files/tekimejew.pdfIn PDF document text
    • http://ip-golubev.ru/ckfinder/userfiles/files/pafuvonulono.pdfIn PDF document text
    • http://mishor-uvk.com/uploads/files/powetudolur.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_off0000e926.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE926 18916 bytes
SHA-256: a1db68853b810b0a3aee74f04bbdc7c78066c8a26767ade2363ab7fde538b206
font_01_sfnt_off00011ad1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AD1 10408 bytes
SHA-256: dbc70f4faf4d865ad5eee6cf6300c227fd8e9011a4e86abb0a07ed4eb9990fbc
font_02_sfnt_off0001325b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1325B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1