Malicious PDF — malware analysis report

Static analysis result for SHA-256 d73f1fe38dd788ff…

MALICIOUS

PDF

80.4 KB Created: 2021-09-24 11:19:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e535380371098b0fb60dbb51a823449a SHA-1: 7f5166be744090f742d1c74d686ed1a652f2be8d SHA-256: d73f1fe38dd788ff3ae30bd6a72c6812aa4f37ef493704dd9d9f16e02e057852
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to compromised WordPress upload storage and other potentially malicious URLs, such as https://cructi.ru/uplcv?utm_term=weather+forecast+premium+apk. The presence of embedded URLs and the nature of the link farm suggest an attempt to redirect users to phishing sites or download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://cructi.ru/uplcv?utm_term=weather+forecast+premium+apk
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16145cc59984f7---wataxivowilogejoze.pdf
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/1614390fdc8810---30058048750.pdf
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/h91rqpb0ieqvqj8i04tu6p6a1h/79251466177.pdf
    • https://highfieldhousehotel.net/nbloom/fckuploads/file/91808553393.pdf
    • http://yangpupark.com/uploadfile/files/72550508642.pdf
    • https://groupekheidri.com/ckfinder/userfiles/files/25919377212.pdf
    • https://member-amz-seller-system.de/wp-content/plugins/super-forms/uploads/php/files/af85d8ec1fe899ecf4279945ef79d9ff/67818461971.pdf
    • https://hiperaktivite.info/userfiles/files/49218964286.pdf
    • https://zagi.hr/files/12235243181.pdf
    • http://stmarysharipad.com/userfiles/file/39676372131.pdf
    • https://gogift-it.com/userfiles/files/kerirukawize.pdf
    • https://toananhmedical.com/uploads/files/viximegosekalalizofafutis.pdf
    • https://www.newhorizonscrisiscenter.org/ckfinder/userfiles/files/biwesilovekex.pdf
    • http://internet-trade.cz/UserFiles/file/2208444136.pdf
    • https://sca-eagleegg5k.com/ckfinder/triplebuserfiles/file/79115432263.pdf
    • http://chia4kids.ru/ckfinder/userfiles/files/85394987586.pdf
    • https://certifiedcollisionrepair.com/home/cert/public_html/ckfinder/userfiles/files/18088689985.pdf
    • http://monarchiaerembolt.hu/tmp/rivokopezake.pdf
    • http://mrhobbscoffee.com/images/uploads/file/15566042486.pdf
    • http://finalbrand.cz/upload/file/rapokexuzujori.pdf
    • http://5thaveseniors.org/userfiles/file/rodunewixefezaxowogag.pdf
    • https://kanat.com/upload/ckfinder/files/57380631591.pdf
    • http://baigeleather.com/userfiles/file/sibalatadipit.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d3d6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD3D6 16792 bytes
font_01_sfnt_off0000ebed.bin
aa1474e9bebe778fa8a9b9dcfb1c45b6f67d13f869530d3f5a530034d0d93222
pdf-font-stream PDF embedded font (sfnt) at offset 0xEBED 10780 bytes
font_02_sfnt_off000104d0.bin
0750878cacb24aba5b18901b449db6096d45499dd9e57fb4f1d2586aa34e2a28
pdf-font-stream PDF embedded font (sfnt) at offset 0x104D0 17928 bytes