Malicious PDF — malware analysis report

Static analysis result for SHA-256 ba4c0891de48698c…

MALICIOUS

PDF

88.9 KB Created: 2021-07-08 13:18:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 2c12d9d2b0a3927d7ff6283c1bfc5d43 SHA-1: b23f3bbf4e9f7c9813c89f02b37a3a936d794744 SHA-256: ba4c0891de48698c3f49733e15fbf99423cab5cf8476db2fe52e2cfc457feac8
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to numerous compromised WordPress sites, indicating a likely phishing or malware distribution campaign. The ML classifier strongly flagged this PDF as malicious, and the heuristics identify it as a link farm on disposable hosting. No scripts were extracted, but the structure suggests the document's primary purpose is to redirect users to malicious external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 5

  • 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=u+words+3+letters PDF link annotation
    • http://photographybynami.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e81dd4c811---11962628344.pdfIn PDF document text
    • http://grupomarsamo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e2d9059472---xatuveruvevijibobuzorusa.pdfIn PDF document text
    • https://wills.sg/wp-content/plugins/super-forms/uploads/php/files/6035e3e3a4baeb57a73d2f5b28b0afb5/98330696925.pdfIn PDF document text
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608b68a31609c---zefuwu.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608942d706c23---18923960552.pdfIn PDF document text
    • https://bachson.net/upload/file/patixumivumixi.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/16085af798c538---latolazokolopef.pdfIn PDF document text
    • http://pressvaluation.net/userfiles/file/luluvu.pdfIn PDF document text
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e3c569cd6c---55471527017.pdfIn PDF document text
    • https://shiphangnhanh.net/uploads/image/files/58526896990.pdfIn PDF document text
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b76c9a7367e---38003135122.pdfIn PDF document text
    • https://slezanie.eu/userfiles/file/75102749042.pdfIn PDF document text
    • https://xn--80aaijzh9b.xn--90ae/documents/file/tulivezakaza.pdfIn PDF document text
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/b2b3548cea5d73f3d3ca817ae1883aed/vagarumikujedep.pdfIn PDF document text
    • https://bem-sa.com/img/file/wowurikilozerizomurawiped.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c2ed41be803---likojiro.pdfIn PDF document text
    • http://global-insurance-broker.de/downloads/43482770998.pdfIn PDF document text
    • https://astek-telem.fr/userfiles/file/96019531558.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/p9suufvtg0htm25k8cagjum3h6/99361449128.pdfIn PDF document text
    • https://big-cash.de/wp-content/plugins/super-forms/uploads/php/files/ih9nitoudgd5puir73fv1lpasv/fubuf.pdfIn PDF document text
    • http://sattamatkapatti.com/userfiles/file/gugizixopenotulafereru.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160aba884cf260---lovodisirodivesatamekud.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160df7ebd242ce---kiwabuxebobepojuvixu.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608102f632d27---16164237129.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_off0000f927.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF927 10148 bytes
SHA-256: 18d61ab09bde05ca363787dff7ef09eb05e7debcb283ff8d2923f372f9e8749d
font_01_sfnt_off00011015.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11015 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012827.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12827 17732 bytes
SHA-256: cecf36c002bbae10f7580ea8dc4f7b6c4afd411faa2bb85ba5556989c03d3fff