Malicious PDF — malware analysis report

Static analysis result for SHA-256 f616409cec20d9e5…

MALICIOUS

PDF

76.7 KB Created: 2021-06-07 01:48:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 00551d22393776d79667c8615c7fb30d SHA-1: 43525312404c37cffa7fa17e11e85580213bf3eb SHA-256: f616409cec20d9e575d150a4dd46ed3d8ee07d9a454884a6bbfa5de5a43cfa0d
156 Risk Score

Malware Insights

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

The PDF file contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, suggesting a link farm for phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document designed to redirect users to potentially harmful content.

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=tabla+de+dosificacion+de+concreto+por+bulto
    • http://eko-inwest.eu/upload/file/47415816927.pdf
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/binufumixiwera.pdf
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/k1ht8lbh9j9vbc84sb7sukulc3/89082069255.pdf
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/4kfqrf2plkp5ipsnh38ldqo1q5/jazeniferefane.pdf
    • https://www.kasekimi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cca403b90d---89117991972.pdf
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a914bd842cf---30368526236.pdf
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/f4cb0574360497bec25025f1438c6c12/gugobiguvarijemedezezitik.pdf
    • https://golf-tout-terrain.com/publish/page/file/zajodezasovamosoku.pdf
    • http://bright-mineral.com/uploadfile/file/2021052115535367.pdf
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/658648cb5a0c27b1a76feadf2c476599/45400680585.pdf
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081e0c6d080d---kasakijafefidinube.pdf
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/cc0c09a957672b7c88241d57dd5b821d/jebuzu.pdf
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a8f5f4851a---tajuwa.pdf
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6d89d5251e---45911209461.pdf
    • https://www.rowtheerne.com/wp-content/plugins/super-forms/uploads/php/files/c5214fad3e5cf78ff3491e652049a7a8/najux.pdf
    • https://pousadamarazul.tur.br/wp-content/plugins/formcraft/file-upload/server/content/files/160817e71458ed---mizidukevufegit.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_off0000de5d.bin
fbd1204f99c9b669a7cfd582f12ab6a2bd06bcefd74089414e4cf73e57365b46
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE5D 5120 bytes
font_01_sfnt_off0000efcb.bin
67192be1c509edf8f8f8c0760a9d2a1a0c9ec82a2342d9015721084cbf3e6e6a
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFCB 11596 bytes
font_02_sfnt_off000115bf.bin
9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2
pdf-font-stream PDF embedded font (sfnt) at offset 0x115BF 4324 bytes