Malicious PDF — malware analysis report

Static analysis result for SHA-256 166d1dc544cea624…

MALICIOUS

PDF

80.9 KB Created: 2021-09-15 19:51:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: bef4571716060f778056255ba604f745 SHA-1: 8c6736fcf08ab9d3e67f969aff55fe7b52cb8d29 SHA-256: 166d1dc544cea624f2487d43dab226f9675c1682148e9b49eb6552e60c5947de
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier. It contains embedded JavaScript, which is often used to exploit PDF vulnerabilities or redirect users. Additionally, it features a link farm with multiple URLs, some pointing to compromised CMS uploads and disposable hosting, indicating a potential phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 http://crm333.com/documentos/file/13328133687.pdf In PDF document text
    • http://sake2metustin.com/uploads/files/78330857493.pdfIn PDF document text
    • http://lexus-custom.com/js/upload/files/gilokubazariza.pdfIn PDF document text
    • http://beloezoloto.ru/userfiles/file/duwafodisogoxifopulotez.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b7cf33a635---48771863583.pdfIn PDF document text
    • http://canxetaidientu.com/images/file/noketoxunujoworavuv.pdfIn PDF document text
    • http://doubler-son-capital.com/photos/files/50970198233.pdfIn PDF document text
    • https://www.solucionaesp.com/ckfinder/userfiles/files/98675301978.pdfIn PDF document text
    • http://abcgsgeds.friendship-match.com/upload/files/nogumowinesepobedadolaxo.pdfIn PDF document text
    • http://magnumprint.ru/upload/files/jiret.pdfIn PDF document text
    • https://smartbrand.ro/mm/file/81224018600.pdfIn PDF document text
    • http://www.giuseppe.ru/ckfinder/userfiles/files/wiwomukuti.pdfIn PDF document text
    • https://mamadona.ru/ckfinder/userfiles/files/38483655183.pdfIn PDF document text
    • https://ghnservizi.com/file/wowalubapuwekuli.pdfIn PDF document text
    • http://bhk-aindling.com/userfiles/files/32420802728.pdfIn PDF document text
    • https://maggievanostrand.com/uploads/media/file/1597780651.pdfIn PDF document text
    • https://abogadosaccidentealicante.centralcms.cloud/galeria/files/89172754771.pdfIn PDF document text
    • http://mexxeopaint.com/upload/files/6845394300.pdfIn PDF document text
    • http://client.diffuse.info/files/xawolakoriladojazero.pdfIn PDF document text
    • http://computer-rudolstadt.de/upload/file/39841808086.pdfIn PDF document text
    • http://showdoimovel.com/files/files/93988309403.pdfIn PDF document text
    • http://autostyle-japan.com/js/upload/files/golom.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fcd00a8764---rolased.pdfIn PDF document text
    • https://trickapotisk.cz/webpagebuilder/ckfinder/userfiles/files/25415691146.pdfIn PDF document text
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/0abd370fa8d8292f9049a6d97c460fb9/susoledazoza.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=best+rally+games+androidPDF 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_off0000d845.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD845 10760 bytes
SHA-256: 49826426beba4f89e4a0c4edac61ae569147aeb6afde9b580b595bd1ea1929a4
font_01_sfnt_off0000f0d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0D6 17320 bytes
SHA-256: 8042cc3c9f290af3c8ec090620748c70616963d66044559940ee3dd762f5d1d0
font_02_sfnt_off00011dce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DCE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1