Malicious PDF — malware analysis report

Static analysis result for SHA-256 88f4da0f21e13667…

MALICIOUS

PDF

80.9 KB Created: 2021-09-15 03:34:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: e4ab589f444fc3c82706e15a9731d772 SHA-1: 3a629952fda8d367aea272cde4180514f4c2192d SHA-256: 88f4da0f21e13667d9df841eab2fefdf7cecb213e7a16ba13c0566a1f284bfb4
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. The presence of multiple external URIs and link farm heuristics supports the classification as a malicious link distribution mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://catamma.ru/uplcv?utm_term=how+to+switch+my+android+to+iphone PDF link annotation
    • http://poornasreehomeoclinic.com/ckfinder/userfiles/files/22171518887.pdfIn PDF document text
    • http://studiotipaldo.com/userfiles/files/60922811791.pdfIn PDF document text
    • https://huanghecables.com/d/files/nemuvopoto.pdfIn PDF document text
    • http://studioagm.it/userfiles/files/87023178939.pdfIn PDF document text
    • https://shopinhome.com/ci/userfiles/files/mefuraw.pdfIn PDF document text
    • http://kdbelektrotechniek.nl/uploads/file/15296450487.pdfIn PDF document text
    • https://morabia.fi/images/file/zipenopawuxitup.pdfIn PDF document text
    • https://everestart.com/images/stories/file/93901648736.pdfIn PDF document text
    • https://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138ef57ddce7---lilefobo.pdfIn PDF document text
    • http://creationart.hu/files/file/64288601567.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/161396b5ef295c---rafosutadubusapagaf.pdfIn PDF document text
    • http://techmechengineers.com/uploads/56768859653.pdfIn PDF document text
    • http://myagreement.com/UserFiles/file/lifarojodopumu.pdfIn PDF document text
    • http://kryotherapie.net/neu/userfiles/file/28604645642.pdfIn PDF document text
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/80a1a6854c9a0ff864a9b959c7f3758b/90342652600.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/161413bd942214---wajovuvovonex.pdfIn PDF document text
    • http://kleinschaden.expert/userfiles/file/gevodoromumibob.pdfIn PDF document text
    • http://dkmmotor.com/files/userfiles/file/mulagetelenepizifolinatet.pdfIn PDF document text
    • http://onthebroadway.com/CPD/adminpanel/upload/file/sevijogugipenoxagur.pdfIn PDF document text
    • https://milsagliksen.org/upload/ckfinder/files/subikotosinimidejovo.pdfIn PDF document text
    • http://popeyebio.com/upload/files/65430126451.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://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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d847.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD847 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f059.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF059 17192 bytes
SHA-256: f176f504634c95cb575aa26a40aa75b5d9e56846f4a34bc9eef144f601447c16
font_02_sfnt_off00011cbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CBE 10924 bytes
SHA-256: 85bc116b49489ba768ef348e6eec5d9a35c85cc0bc0feb256411990a9559a921