Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c7670b619a8f4a8…

MALICIOUS

PDF

79.4 KB Created: 2021-09-18 20:18:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 3959a0ca21d7f9e8c5b120ff799d7f98 SHA-1: a27fe506656b3bbc8a93019c1260aa3b16023bb1 SHA-256: 3c7670b619a8f4a8606376284f0c2d6ad520d5cb266f2faf2cc4ea391c418ff2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The file is identified as malicious by ML classifiers and ClamAV, with heuristics indicating it functions as a link farm. Multiple external URLs are present, some hosted on compromised WordPress uploads and disposable domains, suggesting a phishing or malware distribution scheme. The PDF structure and numerous external links point towards an attempt to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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://highrise.pl/file/14709516177.pdf In PDF document text
    • https://printsolutions.ro/uploads/wysiwyg/files/wukemamefojekif.pdfIn PDF document text
    • https://www.businesswatchguardingservices.co.uk/wp-content/plugins/super-forms/uploads/php/files/rbj73an80u5j8ica8ifhc7vd0q/bazojezare.pdfIn PDF document text
    • http://aftckwt.com/uploads/file/59335857238.pdfIn PDF document text
    • http://polaryachts.com/res/wysiwyg/file/takesavodaf.pdfIn PDF document text
    • http://enotecagaribaldi.it/userfiles/files/4096035648.pdfIn PDF document text
    • http://issaproject.com/app/views/panel/ckfinder/userfiles/files/41510842126.pdfIn PDF document text
    • http://sakaryakasaplarodasi.org/userfiles/file/36003120876.pdfIn PDF document text
    • https://ciar.vn/uploads/image/files/ruvujokazavipujimodine.pdfIn PDF document text
    • http://studiotecnicodama.it/userfiles/files/85053007339.pdfIn PDF document text
    • https://damsindia.org/admin/uploads/file/tizopasanuvudeguvepopuk.pdfIn PDF document text
    • http://medizator.ru/ckfinder/userfiles/files/lafesorikibilatem.pdfIn PDF document text
    • https://nikoljski.com/ckfinder/userfiles/files/73182935366.pdfIn PDF document text
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/161311fe91497a---vejukavubakanozefo.pdfIn PDF document text
    • http://www.amedna.com/userfiles/files/tuninuridofadikaponuso.pdfIn PDF document text
    • https://sokolzgierz.pl/web/uploads/files/bekilefebinukolux.pdfIn PDF document text
    • http://vibrobreaker.com/files/files/22450206025.pdfIn PDF document text
    • http://scissortailfarms.com/wp-content/plugins/formcraft/file-upload/server/content/files/161409e864b71a---49372426312.pdfIn PDF document text
    • http://belniig.by/public/file/9320011096.pdfIn PDF document text
    • https://perfectsextherapy.com/public_html/userfiles/file/gigalibid.pdfIn PDF document text
    • https://baigiangtoanhoc.com/upload/files/dugugifilelawerevagowe.pdfIn PDF document text
    • https://verlauf-ekb.ru/admin/ckfinder/userfiles/files/23586816982.pdfIn PDF document text
    • http://lnyuanzong.com/uploads/files/20210918062921.pdfIn PDF document text
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/f4c27cd79f920710868281c15c832e23/ritelon.pdfIn PDF document text
    • http://birdwatching.sk/media/file/57695127668.pdfIn PDF document text
    • https://madspot.dk/ckfinder/userfiles/files/foximavizuj.pdfIn PDF document text
    • http://officeharbor.com/pdtInfo/72846721947.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=yellow+%26+purple+makePDF link annotation
    • 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_off0000d590.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD590 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eda2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDA2 17764 bytes
SHA-256: dcd8539eb301362c3f1a1fd566efb66d722345b4ba671589d0bf9b4a821a2c4d
font_02_sfnt_off00011c0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C0B 9440 bytes
SHA-256: 2b7cdcd670d4a6999c10fd88b7fb442b52e4f46eb8802f4dfa3d3a2031272696