Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb3b7339cf31df6c…

MALICIOUS

PDF

98.5 KB Created: 2021-06-25 16:04:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 686843efeda2b05cde24728e2baaf27e SHA-1: d5fb4968cb4b254d2884e4695fa512e374ac5f2e SHA-256: cb3b7339cf31df6c89c32b3b43e52a774a92dd8866662856e0258dab00c16f21
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised WordPress upload directories, suggesting it's part of a link farm designed to distribute malware. The presence of a 'download button' heuristic further supports the phishing lure attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://crewmak.ru/uplcv?utm_term=the+next+life+as+a+villainess PDF link annotation
    • http://thegioidahoacuong.com/uploads/image/files/didosupitato.pdfIn PDF document text
    • http://cocoal.com/uploads/file/wunigotodofun.pdfIn PDF document text
    • http://www.jamesbgriffinlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090db99c15cc---fozokirol.pdfIn PDF document text
    • https://mobistore.co.nz/wp-content/plugins/super-forms/uploads/php/files/1bb3492174579c938bd457a0ba492860/diribajiniwotitisidawetu.pdfIn PDF document text
    • http://www.hangmandigital.com/files/file/rawerufolexodol.pdfIn PDF document text
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab39f675e3b---linezeziwuwimomagowu.pdfIn PDF document text
    • http://littlepearlspublishing.in/data/eimages/file/saxelivoponuvod.pdfIn PDF document text
    • http://harissarantis.com/userfiles/files/nogewetagevadovobax.pdfIn PDF document text
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160bfa490a98c0---gubunotirimu.pdfIn PDF document text
    • https://socialchangefactory.org/wp-content/plugins/super-forms/uploads/php/files/d62e28bc707730ec2d7ed5dea743176f/povatasofidemip.pdfIn PDF document text
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/23f15c4d439538734419bc08e2cded61/56917101277.pdfIn PDF document text
    • https://iominneapolis.com/wp-content/plugins/super-forms/uploads/php/files/0c108a281db644dae992bcc8cf9a5d16/kinom.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087860960cde---nekitarasom.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/9814dd3cede8ca1242b3db665cd75399/sebuxewemipebuzuv.pdfIn 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011ad2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AD2 17120 bytes
SHA-256: daf1d7528150c0d50298f5476eb31c7fd5bccb0f8f7efded6c0458f159143b6c
font_01_sfnt_off0001472c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1472C 2960 bytes
SHA-256: eb88635f307a8be3ad8acd3b70ecde0e8bc3dc312dfc9311f211d6116a886d59
font_02_sfnt_off0001537f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1537F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off00016b96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16B96 10224 bytes
SHA-256: b5cd7b673c8e57794122cee8e375f1c427d27f2f04d4000f7efedcb6305fb4b1