Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc01a4eda31ad5a9…

MALICIOUS

PDF

77.7 KB Created: 2021-09-08 12:18:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 9db01930b23977bdb72474c0346fe26a SHA-1: 368e330a99b134c7ee39b3ba56457c67d22fc359 SHA-256: dc01a4eda31ad5a95e9d26594415fa598fdc74413e29d80cf75f6b06261ca4e2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to compromised WordPress sites or disposable hosting, suggesting a phishing or malware distribution scheme. The presence of embedded URLs and the nature of the heuristics strongly suggest this file is intended to redirect users to malicious content, likely as part of a spearphishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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://chcial.ru/uplcv?utm_term=word+em+pdf+ilove PDF link annotation
    • http://regimhotelierbucuresti.com/images/userfiles/25479853511.pdfIn PDF document text
    • http://xn--h1aaebajlcgx.xn--p1ai/sadm_files/87418884210.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16134bcf82c4cb---nirixokagelu.pdfIn PDF document text
    • http://parbatsamajjapan.com/img/files/files/bazof.pdfIn PDF document text
    • http://awfiowv.love-mrt.com/upload/files/74755196707.pdfIn PDF document text
    • http://jfe.hk/userfiles/rulurobuti.pdfIn PDF document text
    • http://studiodabo.eu/userfiles/files/guxukorowozigewurewone.pdfIn PDF document text
    • http://dbcasagayathottam.org/assets/uploads/cms_images/files/sajagufefeneza.pdfIn PDF document text
    • https://venusnvs.com/userfiles/file/wibumakiwabapib.pdfIn PDF document text
    • http://teplorium.su/userfiles/file/49391528498.pdfIn PDF document text
    • https://alebusph.centralcms.cloud/galeria/files/xoresuta.pdfIn PDF document text
    • http://3asoft.vn/img/files/sodel.pdfIn PDF document text
    • http://kipia-nn.ru/userfiles/file/modijizizo.pdfIn PDF document text
    • https://eagleegg5k.com/ckfinder/triplebuserfiles/file/tiwituruf.pdfIn PDF document text
    • https://securitydm.net/slicice/file/35066648868.pdfIn PDF document text
    • http://home-plast.ru/foto/files/58098767832.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/161384952658f3---bexugu.pdfIn PDF document text
    • https://dp-engineers.com/admin/userfiles/file/49569422919.pdfIn PDF document text
    • http://maidichike.com/upload/files/64407511416.pdfIn PDF document text
    • https://a-guskov.ru/uploads/files/8631811154.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/ac8109dec913d17b5fc2e4212b8631ad/26916918299.pdfIn PDF document text
    • https://tims.ro/ckfinder/userfiles/files/ritajakutegokefinipipit.pdfIn PDF document text
    • http://peknanevesta.sk/media/file/97108648812.pdfIn PDF document text
    • https://corpusbg.com/files/fck/file/766588729.pdfIn PDF document text
    • https://serrechevalier-skifun.com/imagesfile/92622069258.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_off0000cd8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD8A 17196 bytes
SHA-256: e7eca6a53a6d768f83b0f0d033aa645e7641fd0cbf683eeeb2791cede8da8161
font_01_sfnt_off0000fa87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA87 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001129e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1129E 10184 bytes
SHA-256: baefa653d824522a546b0dfb6c40cf95659b0b10d5b7ec6823dc0ee60a23ff88