Malicious PDF — malware analysis report

Static analysis result for SHA-256 fdb99c6dac3e1b5f…

MALICIOUS

PDF

80.0 KB Created: 2021-05-28 11:27:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 008499feabbad85acfc4754e8491f08b SHA-1: 186dd755c1ff2d17bf8714d806ba8411885ca6e8 SHA-256: fdb99c6dac3e1b5f4ee937f78c20e39aba6b6e716c1000f38920ad5153a52a5f
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://cructi.ru/uplcv?utm_term=how+to+fix+call+of+duty+mobile+google+play+error
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072570023054---55523066938.pdf
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0501fdb7a0---dokogafuforu.pdf
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/3778b30210e05f196fe5bea93cbc6c4a/3728250264.pdf
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160777c73455fe---68088075086.pdf
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/a2d646dad9916d9c85839855b11b1157/derimigasu.pdf
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1608280f3892d2---pavafuwafagozila.pdf
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c0d6d7e956---zetetinuzugunutodelafu.pdf
    • http://kimbuunguyen.com/uploads/userfiles/file/gofokomijigepupamu.pdf
    • https://advancedcheckcashadvance.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071b6d660d19---47483937774.pdf
    • https://www.reflectionuk.com/wp-content/plugins/super-forms/uploads/php/files/7l070tiluegrq7qcpt6qs0jpgm/48490486702.pdf
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16070817431fab---61440934621.pdf
    • http://bycongroup.com/UserFiles/file/64582149139.pdf
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/ajbir4vi2kttc3lunpgcjaj5on/gexojijokowetika.pdf
    • http://ahcxdq.com/uploads/file/25154131347.pdf
    • http://hi-reid-solutions.com/wp-content/plugins/super-forms/uploads/php/files/fbc835cec3e03f9d82a7621b33e9690d/40427000176.pdf
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/1606faeb0b7a1d---5065036352.pdf
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160753e31c9949---78855712306.pdf
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/160982daf77008---xoguzadebuji.pdf
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/brstq5rp4mfc9c39ctjll49tbr/20735259935.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ed61.bin
acf0445efb6d06d17defd51e371ce93edf4b9ac29591043e45a3c2df73920289
pdf-font-stream PDF embedded font (sfnt) at offset 0xED61 5436 bytes
font_01_sfnt_off0000fffc.bin
00eee88c796aa40307ab1ce11834ff03f4f6604afa834082d36dc62df68e6943
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFFC 10556 bytes
font_02_sfnt_off00012401.bin
ce7e2e230a41ba6fc2d7d2240890c8289d67876d84a3d076d67c0b48111c8230
pdf-font-stream PDF embedded font (sfnt) at offset 0x12401 4324 bytes