Malicious PDF — malware analysis report

Static analysis result for SHA-256 1310698c3b0cfcb7…

MALICIOUS

PDF

128.3 KB Created: 2021-06-15 10:57:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: d492851cf5d07cf16835516901d46047 SHA-1: 4f60c438f1d41c6a40d18efc66c418ba8ebf8943 SHA-256: 1310698c3b0cfcb78836c4cdb3a3265d86f643d26cbd71fe3c9f7ba5a329cd83
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The presence of numerous external URIs, many pointing to compromised CMS upload storage and acting as link farms, suggests a phishing or malware distribution attempt. The document body, though heavily obfuscated, contains references to 'wkhtmltopdf' and a date, indicating it was likely generated programmatically to host these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

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://garglob.ru/uplcv?utm_term=a+rose+for+emily+by+william+faulkner+pdf PDF link annotation
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16075d695652ef---29199204561.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a030e03f62---97533747253.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/01f1ea1912dadb2d6f8a5ec06f43396f/59013413261.pdfIn PDF document text
    • http://bellezaeimagen.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1607ad6de3f653---24618634879.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/1608f982b6c145---zewosonesadijikixozitu.pdfIn PDF document text
    • http://cuboni.com/uploadfile/hong202106071230528172.pdfIn PDF document text
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/f01d4eeb87eab732f1a3de97e844d987/40549502962.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2c794d780e---bogudapawidimuxowe.pdfIn PDF document text
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d4686bcde0---49209328867.pdfIn PDF document text
    • http://fecirturizm.com/resimler/files/mubujalagomubevinilosesu.pdfIn PDF document text
    • https://noddy.nu/images/file/robakowobojovuwidefuk.pdfIn PDF document text
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/024d01be61a7f6fb8c2863bdf88172e5/pifevafosofofimopef.pdfIn PDF document text
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c85a460861f---wumijezawuruzidixuduxo.pdfIn PDF document text
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/3mq7afh2ha1nn0g3ao7eol2kp8/77365338697.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a15859307df---9808100946.pdfIn PDF document text
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/f6072f35fbd04698595166ae493221aa/681163036.pdfIn PDF document text
    • https://cuisinescartier.ca/upload/editor/file/8761439714.pdfIn PDF document text
    • http://www.rose-for-emily.com/In 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://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001ab26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1AB26 5576 bytes
SHA-256: 08dda2127f3b428e9b5362038905d66abd8ef3e449859314d4b27d936414d78c
font_01_sfnt_off0001be1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1BE1A 24316 bytes
SHA-256: 1385f4aa2bc02cafa2da777bdcf22260f37ffbdfe28b73042f51eef0fa4fef48