Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b407730a2f9df13…

MALICIOUS

PDF

93.0 KB Created: 2021-07-03 05:06:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 34b1e5bae70b45d362c16f288e22273b SHA-1: a818c2f53bf34138cf04355f0f95320ece8e3e41 SHA-256: 7b407730a2f9df13fab82f06e25e76574f0dc783ee0dcd20a60502c663bdcf79
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised WordPress sites, suggesting it functions as a link farm to distribute further malicious content or phish for information. The presence of external URIs and link farm heuristics strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://krisoc.ru/uplcv?utm_term=most+elite+military+in+the+world PDF link annotation
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/n3trf9djdcvohb3in3cnp73mdu/98316100541.pdfIn PDF document text
    • https://seikai.jp/free_images/files/fuderafukuka.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/160941129799d7---66513735600.pdfIn PDF document text
    • http://zawayakw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ceccc3ef10---20498256433.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/86fdc0955c1fef54457e7bb92a2a3bb6/kezuvemugof.pdfIn PDF document text
    • http://mmckno2010.zkosuchdol.info/files/kekeruvurav.pdfIn PDF document text
    • http://vamaconsulting.sk/userfiles/file/janotu.pdfIn PDF document text
    • https://pacpartner.net/images_client//imagesfile/74988463858.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8952576cfb---31886670549.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9a47142b5---39474912988.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fc8c3a47eb---xikujuboj.pdfIn PDF document text
    • http://beergolfers.com/blog/images/file/gixopejarugulip.pdfIn PDF document text
    • http://leebyunghun.kr/new/upload/board/files/52303031513.pdfIn PDF document text
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/53a0e446e11b57cfaaa3a9964e074d69/tasuja.pdfIn PDF document text
    • https://aptitudeclass.com/ckfinder/userfiles/files/xegan.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be81d4c62a6---wojejinelikidi.pdfIn PDF document text
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/b3a73043ed8abfe3e8e5e8421280528a/18877123125.pdfIn PDF document text
    • http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/u9qgibetko7i196rguf14s9hq5/supaviremow.pdfIn PDF document text
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/160bb2f35de85e---tabovipo.pdfIn PDF document text
    • https://ph2020.org/FCKeditor/file/janevamibodufulu.pdfIn PDF document text
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/gn9bl4ddb7cdv8shuc1v4bo6g4/44777602482.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ea66c46ab2---55019436576.pdfIn PDF document text
    • https://www.rekalibracija.com/wp-content/plugins/super-forms/uploads/php/files/8dea940aad683e72e7f12f727a0be14d/56563450287.pdfIn PDF document text
    • https://bowenpainter.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e4fc44728a---24760750148.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_off00010839.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10839 10704 bytes
SHA-256: e5be2f30baae307dfcb6f3165a8d901a0e108d238e5d5014e9e75bf415517e97
font_01_sfnt_off000120a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120A6 17140 bytes
SHA-256: 7891a71510c6af2c63d356f3e9428c336e491b8f07c2e874f4a2c9b9025a501f
font_02_sfnt_off00014ce1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14CE1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1