Malicious PDF — malware analysis report

Static analysis result for SHA-256 5671835ad99c06d8…

MALICIOUS

PDF

73.4 KB Created: 2021-06-22 10:25:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-26
MD5: 35b113bfef3a1ecefcb0a0ba3fc0fbeb SHA-1: 40fbea869f8bda83652225afceb570400be6ac94 SHA-256: 5671835ad99c06d81c1cef5043f0dac1ef4c11c9b530bfd4184fc770abade834
156 Risk Score

Malware Insights

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

The PDF file contains numerous links to compromised WordPress sites, disguised as a 'road construction cost calculator'. The ML classifier and ClamAV heuristic strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and embedded links suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://winston-woodward.com/wp-content/plugins/super-forms/uploads/php/files/178d87723b50aa37137c031a16fc0bdc/17671389318.pdf In PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1606c852feb95c---xukuredakazid.pdfIn PDF document text
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/18e1a10a764f5cd2bb95b43fa32f8fb6/54688751629.pdfIn PDF document text
    • https://www.rydalmereprestige.com.au/wp-content/plugins/super-forms/uploads/php/files/om3tuhe9o7lu0ma8nrpnn66u5e/vunikarisu.pdfIn PDF document text
    • http://youngshiny.com/userfiles/file/1624004441.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/2cd2ed17f32c4370c80b31b6b3fac530/46075957428.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/16077fa3c945c6---37561697314.pdfIn PDF document text
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160702c7bb90de---zepebelobosugok.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bc8a8a48811---49324362281.pdfIn PDF document text
    • http://alpanelektrik.com/depo/sayfaresim/file/jizane.pdfIn PDF document text
    • https://jodhpurtravels.com/nbloom/fckuploads/file/34561112717.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/160972c0fd630a---10407097977.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/160b0fd4a5234e---losodaxejujin.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/284bc83d628b79b310a50631c95e5223/48338714415.pdfIn PDF document text
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/160868b2667616---jixiwirutadufoniguxume.pdfIn PDF document text
    • http://www.magicapro.it/wp-content/plugins/formcraft/file-upload/server/content/files/160707b0d53c5b---pamadevabadulatedizibug.pdfIn PDF document text
    • http://www.medicellbank.com/userfiles/files/tilej.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=road+construction+cost+calculatorPDF link annotation
    • 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_off0000e301.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE301 4940 bytes
SHA-256: cbaf7581789d1f647f36765062d090607ea55efc60c6269fa34b1ae5bddbe622
font_01_sfnt_off0000f3dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3DD 10748 bytes
SHA-256: 3fec2150123d858603f2ac54a820d0abfb15576d34dc2d15766e84de62ad1a92