Malicious PDF — malware analysis report

Static analysis result for SHA-256 976ee86fc5f27450…

MALICIOUS

PDF

79.2 KB Created: 2021-09-07 10:59:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: ef8317127603836a0b4f99296ed15caf SHA-1: e03ef955c3e06c29ca179ebac82d04c29a626f0c SHA-256: 976ee86fc5f27450372a96c0f8cca1b5311698ae087c4c0c15898fe3479625ed
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample is a PDF file identified as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised WordPress installations or disposable domains, suggesting a link farm designed to redirect users to malicious sites. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of using such domains for SEO manipulation or to host malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://crewmak.ru/uplcv?utm_term=ndt+standards+pdf PDF link annotation
    • https://regeneracion-capilar.com/wp-content/plugins/super-forms/uploads/php/files/c9e7f38198ca0742f0e792ba53155c89/82043981057.pdfIn PDF document text
    • https://damsindia.org/admin/uploads/file/19354911410.pdfIn PDF document text
    • https://hotelmitrutarija.com/uploaded/files/pidawixasizofeb.pdfIn PDF document text
    • http://heathrowairporttaxi.website/userfiles/file/suwemizaveboben.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606fa0277c24a---rajiwekafosutipevekifuzup.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077904b8e031---tonunatuw.pdfIn PDF document text
    • https://carparts-fixture.com/file/file/nigojimipilexukiburago.pdfIn PDF document text
    • http://cnpair.com/userfiles/file/43897809237.pdfIn PDF document text
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/34b3d8fb542dc4c84979dc69698a769a/51396123599.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/11686264831.pdfIn PDF document text
    • http://fipjp.com/userfiles/file/21585507998.pdfIn PDF document text
    • http://kath-kiga-bw.de/bilder/berichte/file/57910244945.pdfIn PDF document text
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a3a32ea8748---mibopumofidugumububine.pdfIn PDF document text
    • https://vmwarts.com/ecovic/file/sisoladejekew.pdfIn PDF document text
    • https://portugaliaimagyarok.com/ckfinder/userfiles/files/nezesipozuwujorus.pdfIn PDF document text
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/1608bcd92b50cb---20068323198.pdfIn PDF document text
    • http://ylplj.com/ckfinder/userfiles/files/93752079530.pdfIn PDF document text
    • https://boyanbolyarski.com/userfiles/file/69273912766.pdfIn PDF document text
    • https://codecs.roimages/file/10125651065.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/a4476fe2814767f247ee5a4624b90cad/rakukazejuna.pdfIn PDF document text
    • https://noddy.nu/images/file/vafijurenevovajawufigenex.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_off0000d54c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD54C 16976 bytes
SHA-256: 5b83e3ab68f98591245a78729c2e22a672442792b9b4b6506e669bfba4267331
font_01_sfnt_off00010146.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10146 10076 bytes
SHA-256: a722a5a66180926a915db3bdbe55b28c3bfc930a5e4d2644f6edbc905111b07f
font_02_sfnt_off000117c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1