Malicious PDF — malware analysis report

Static analysis result for SHA-256 d29dde1a16fef4db…

MALICIOUS

PDF

83.7 KB Created: 2021-09-14 12:56:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: d42a90c3a987f258b532211c08aaf0bc SHA-1: 884b54046c643ba20d499baf5399af0502c81b9f SHA-256: d29dde1a16fef4db0d16e92c1614176e000fcd3142dd780ec22afeecf4eb1800
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many of which are hosted on disposable domains or compromised CMS uploads, suggesting a phishing or malware distribution campaign. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' further supports this, pointing towards the document's role in directing users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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=voice+fx+apk PDF link annotation
    • http://vattucongtrinh.com/userfiles/file/74677707251.pdfIn PDF document text
    • https://zbmbudomont.pl/userfiles/file/21121062346.pdfIn PDF document text
    • http://be-now.pl/userfiles/file/mutava.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1613f87ffb99f4---69595807723.pdfIn PDF document text
    • https://at-studio.tw/app/webroot/userfiles/files/20210901_072334.pdfIn PDF document text
    • https://mami-m.com/Uploads/userfiles/files/gazuge.pdfIn PDF document text
    • http://hyundaihungthinh.com/uploads/images/files/wepezof.pdfIn PDF document text
    • http://sbriz.ru/userfiles/file/25435280559.pdfIn PDF document text
    • http://etpatatietpatata.com/userfiles/files/18002861382.pdfIn PDF document text
    • http://johnmarzillier.com/ckfinder/userfiles/files/42842967448.pdfIn PDF document text
    • https://terminal.hr/userfiles/file/50744303412.pdfIn PDF document text
    • http://allineers.netlovestories.com/upload/files/tevirumu.pdfIn PDF document text
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/58adc94df2cac92a2b6d201743053620/nizafevit.pdfIn PDF document text
    • http://sdsenlex.com/upload/files/10499564515.pdfIn PDF document text
    • http://sarkar.ie/userfiles/file/garibo.pdfIn PDF document text
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/9f13146a14911f1bedf9a3c440911602/75547284230.pdfIn PDF document text
    • https://areicon.com/images/file/31631043542.pdfIn PDF document text
    • http://studiotecnicopinto.it/userfiles/files/50366633504.pdfIn PDF document text
    • https://zemtechnika.lt/public/site/0files/7455794367.pdfIn PDF document text
    • http://manavpublicschool.org/manav/userfiles/file/30691215092.pdfIn PDF document text
    • https://melnikhouse.com/userfiles/file/nepobebizir.pdfIn PDF document text
    • http://lpsa.cz/userfiles/file/wafuvubizudumelobijav.pdfIn PDF document text
    • http://mwflower.com/upimagesfile///46606437046.pdfIn PDF document text
    • https://homestayhoian.thamtuddt.com/uploads/image/files/gakukederebenaxumirefoxi.pdfIn PDF document text
    • http://vititanon.com/user_img/files/bolufukewasaxonimo.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_off0000db1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB1C 10120 bytes
SHA-256: 618dd12acf6b71977b5f2f382b73a45ddd9d185cc137af32ec33d53b47c8be32
font_01_sfnt_off0000f1e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1E2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000109f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109F4 21136 bytes
SHA-256: 274f2b55068a70e9b4a26f7ac76fdb10a8935fb7c73815d169dd2a18447f51d9