Malicious PDF — malware analysis report

Static analysis result for SHA-256 646a668b646ab6c5…

MALICIOUS

PDF

80.8 KB Created: 2021-06-07 22:24:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: e45ad63561ad8a96ddc023da7f47cb5d SHA-1: 788cb77a46448285018f76dff5367ad75996c201 SHA-256: 646a668b646ab6c54512905f38bdeffe00cdfe74d301865320eee9b7bfc8d963
156 Risk Score

Malware Insights

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

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 0.9997

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://crysiq.ru/uplcv?utm_term=acca+p4+course+notes+pdf+free PDF link annotation
    • https://takeorders.online/wp-content/plugins/super-forms/uploads/php/files/b45d9e8b31fngfjna9b1ti56n5/misomuxivete.pdfIn PDF document text
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/b41510e44920cadd1f41a9e1197253c6/zipep.pdfIn PDF document text
    • http://taskentcompany.com/userfiles/file/2579019990.pdfIn PDF document text
    • http://vonkoenigsmund.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb678b4038---35650684894.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/160bb55e4d7e6a---valawuvewedidopid.pdfIn PDF document text
    • http://a-swiss.com/upload/userfiles/file/9976489381.pdfIn PDF document text
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/af8193f6368a1f2bd46e0d84352c0567/86205383015.pdfIn PDF document text
    • http://dekoblickfang.de/userfiles/file/70513099834.pdfIn PDF document text
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/160879a7749d90---tekaxi.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/16080cbc91c778---72063602048.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7fdf94ce1---36173254123.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082af38ebc81---24610585265.pdfIn PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608729ec04cca---gelosaj.pdfIn PDF document text
    • http://nappsa.org/userfiles/file/56834230505.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e157.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE157 5196 bytes
SHA-256: e89fc38d77ccf8dbebc7426dedfdd5bea55bf74bea587191d7f10fdbaa2f275e
font_01_sfnt_off0000f312.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF312 2472 bytes
SHA-256: 203059f004631094afc1c26962954d4d624067d4ba7600eaa91204f6a88510eb
font_02_sfnt_off0000fdf3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDF3 10444 bytes
SHA-256: dc955357ddcce2687b700a07b7f4c8c7a44a47bc09baebc8216eebc839d7f9f6
font_03_sfnt_off000121a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121A9 16344 bytes
SHA-256: ed45a24507f18daeaf6b6e9cac20235e9e43bed88bc2d44b7621eff085e31190