Malicious PDF — malware analysis report

Static analysis result for SHA-256 547890a8f8c0abc3…

MALICIOUS

PDF

74.6 KB Created: 2021-07-06 22:51:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: eb2f4165b1fdfade7eabd310fc49fbbf SHA-1: 2388dcbd7456577fc3cdfaf174a7fc5ca82d17ed SHA-256: 547890a8f8c0abc302b83101cfe0047719842cd8aea549963df5110e86be62a7
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ML classifier strongly flagged this PDF as malicious, and the presence of external URI heuristics further supports a malicious intent. While no scripts were explicitly extracted, the overall structure and URL distribution indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://krisoc.ru/uplcv?utm_term=10th+tamil+book+answers PDF link annotation
    • http://fujiya-la.com/uploads/files/sunikizap.pdfIn PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/49ca6819a6fec940a34810a2f3d6608f/20279157328.pdfIn PDF document text
    • http://akifkasaboglu.com/esatfisek/images_upload/files/24935932241.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/0n29m0htuklknkrnmcqhrg7q9g/kifazarodojafoluniti.pdfIn PDF document text
    • http://tutaylamhet.com/storage/ckfinder/files/96362184000.pdfIn PDF document text
    • https://thetitangroup.ca/wp-content/plugins/super-forms/uploads/php/files/164d53ae34795d2bdb4f88c067c27bb2/81255253054.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/1aa29bc4f8a144316d54c88a758d4bb6/zomisikozaxabokewagib.pdfIn PDF document text
    • https://tisuputih.com/contents//files/5239091266.pdfIn PDF document text
    • http://anhuicrew.com/upload_fck/file/2021-5-12/20210512025107270218.pdfIn PDF document text
    • http://mjacz.cz/soubory/files/64695340911.pdfIn PDF document text
    • http://horlickhigh61.com/clients/a/ab/ab3fb267cc30d45b98f460a20cee0b8d/File/fozekutofeluj.pdfIn PDF document text
    • http://mn-print.ru/ckfinder/userfiles/files/besekagomafezi.pdfIn PDF document text
    • https://www.oasipizza.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c7201e9358c---rewepezosirefum.pdfIn PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/16088861b9d121---woditoj.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/03af1de2cc1e88861aad8a8a0949328b/vajexam.pdfIn PDF document text
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/1607f2fd188b41---37392213008.pdfIn PDF document text
    • https://www.icslights.com/wp-content/plugins/super-forms/uploads/php/files/ba78b4818e5c55dcd0691f6692d9b968/pogonavutonulufosofoke.pdfIn PDF document text
    • http://shophouse.info/images/files/xamul.pdfIn PDF document text
    • https://weyergans-hcc.lv/userfiles/file/fudin.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160b5b418b0703---konedinowu.pdfIn PDF document text
    • https://advancedcheckcashadvance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fb45d0886e---30838284050.pdfIn PDF document text
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/abcnlqq0llh2mi88jmctrf8a76/56769744685.pdfIn PDF document text
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/67dd8ee946452591065cab643d4fbc11/37408331506.pdfIn PDF document text
    • http://renovator.cz/files/file/52011317166.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_off0000c13c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC13C 10768 bytes
SHA-256: 401355943012014e7f747fce4d2c1e7621b7cba2c5158ef39ff11e647859410b
font_01_sfnt_off0000d9e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9E4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f1f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1F6 16708 bytes
SHA-256: b69a0e674aa133b935ee9ee332a9951486cf71d9cae57907a95bcc50f3127eab