Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5d40bd49378801e…

MALICIOUS

PDF

88.1 KB Created: 2021-06-06 21:33:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: 975658e128b8883b79653812f5c44c19 SHA-1: 58bf2c00af78f14fd40c004f7670136e3f6c876c SHA-256: f5d40bd49378801e5122b4ee0c2af1f3194b509459793a03dda46b1405034159
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous links to external websites, many of which appear to be hosted on compromised WordPress installations or disposable domains, suggesting a link farm or phishing lure. The document body, though heavily obfuscated, contains metadata related to its creation by wkhtmltopdf and a title that mimics a search result for a PDF document, reinforcing the phishing or malware distribution intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://smidgel.ru/uplcv?utm_term=as+etapas+do+pensamento+sociol%25C3%25B3gico+karl+marx+pdf PDF link annotation
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/1607bcbaa681b6---54047942071.pdfIn PDF document text
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/wunozalivujejup.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0782f0c2f3---joketezenanugenadalev.pdfIn PDF document text
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/ea09304559d4ea9cea6c05e2ea53e2b5/86686881510.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/160773c1bbf64d---sasodaxapupa.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/160805170099d9---bovabazulikowokajujaw.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/934a40062b8e8549cee008475c687841/fegokunuzixosixi.pdfIn PDF document text
    • https://amd-export.com/site/upload/file/xixejefumofomojifuk.pdfIn PDF document text
    • https://funkydrop.shop/wp-content/plugins/super-forms/uploads/php/files/b69a787fa0f98f2049db6bd6c1a16cb7/tisiredumemozazavamevewib.pdfIn PDF document text
    • https://traonguoc.vn/wp-content/plugins/super-forms/uploads/php/files/2p3o91b5vhnabm46rpe5cotngh/zajazita.pdfIn PDF document text
    • http://fantalife.nl/userfiles/file/xisixokavujizoxu.pdfIn PDF document text
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ceeb40e6ac---demudekofidiretuvusis.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/u7fo5vqdjrmq2md3cdghc785o1/36247451579.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0546859d8b---54532913208.pdfIn 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_off00011549.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11549 5732 bytes
SHA-256: 8a3c5aebf95c279c75bd2df56c7bbf64a5f719128edaa25bcf4d0d32e52c8eaa
font_01_sfnt_off00012889.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12889 13820 bytes
SHA-256: 391bd5aa733932b8c37e97373d92dffbd82329fa4232d015f2993d019c1dc78f