Malicious PDF — malware analysis report

Static analysis result for SHA-256 51b759ebedacc18a…

MALICIOUS

PDF

85.2 KB Created: 2021-08-24 10:55:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: e15f0b98287c525456a6f3c4446e1c7e SHA-1: d7d8c7851f36d16d8bcd60e17ca14f0f4403b513 SHA-256: 51b759ebedacc18a2c6f7d4425b88461057c6f4d78fa07644f7d98bd198489b6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099d426b4e94---sejora.pdf In PDF document text
    • http://maychaybocaocap.com/app/webroot/uploads/files/misulinuzeraxirekifito.pdfIn PDF document text
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076cc5453689---94895170470.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/160f6b4e47362a---36599473300.pdfIn PDF document text
    • http://fonnepal.org/userfiles/file/zezosawujekabet.pdfIn PDF document text
    • http://szwygs.com/upload/26566949336.pdfIn PDF document text
    • http://ksnjl.com/userfiles/files/pufegobolimozi.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609f9c5d4d765---66164976927.pdfIn PDF document text
    • http://mebco.ru/images/file/rabajo.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607b705a37e0a---tifirudelorig.pdfIn PDF document text
    • http://ginzaramen.us/uploads/files/17685589429.pdfIn PDF document text
    • https://dom4m.com/userfiles/files/93577683185.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/4f4d7da2035fe76b6ae616ae7da7884d/kariwalalojarotanod.pdfIn PDF document text
    • https://henklinders.nl/henklinders/upload/files/bowarigobubetosuxik.pdfIn PDF document text
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/317d4a86a5d0c285eb817db00e24a4d4/fexipafutoxiku.pdfIn PDF document text
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/4f4a0055da9aab7158562ac68d3778d7/63103389409.pdfIn PDF document text
    • http://fgsconsulta.com.br/ckfinder/uploads/userfiles/files/61813624517.pdfIn PDF document text
    • http://paillasse.hu/userfiles/file/fivepefupogogavuxawetekok.pdfIn PDF document text
    • https://everywheregenes.com/uploadfile/qu26_qu106_com/files/jodorul.pdfIn PDF document text
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/439380fcc79658d4f89a1d3de7c8377f/76369871934.pdfIn PDF document text
    • http://drstevealbrecht.com/wp-content/plugins/super-forms/uploads/php/files/14e67a033e78a07c8d1fb98a30e60c2f/pogukagavubojibonem.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=fanaa+movie+download+400mbPDF link annotation
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160debd2fda9b1---nibutagusuwoxojozobodi.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_off0000eb01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB01 10512 bytes
SHA-256: a4e2603e41ae17c730c148d498af0b6e027dbc5d169dadfd5b4738fac7d66ece
font_01_sfnt_off000102df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102DF 16764 bytes
SHA-256: 1ae7dc614a1534c44ab6bbda6e213cde182e3aca73042617a52aeae35c70182a
font_02_sfnt_off00012e71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E71 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1