Malicious PDF — malware analysis report

Static analysis result for SHA-256 824d5d0e9e125a61…

MALICIOUS

PDF

75.2 KB Created: 2021-09-16 12:12:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 583bd41153f4358c017d6c59ac144c0c SHA-1: a05748fb999664abe319d33c13583247256cd48c SHA-256: 824d5d0e9e125a612b8e732343dfa1943edc642c6c8ac99ed9512839906e903a
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, and exhibits characteristics of callback phishing or tech-support scams by prompting the user to call a phone number. The PDF contains numerous embedded URLs, many of which point to disposable hosting or link farms, suggesting a broad phishing or scam campaign. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of malicious intent, likely to redirect users to further malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://laborke.ru/uplcv?utm_term=android+phone+reset+google+account PDF link annotation
    • https://siliconautomation.com/userfiles/file/41012570973.pdfIn PDF document text
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/16136afc7bb310---pidavajapamorisiwibixixug.pdfIn PDF document text
    • http://ylphs.com/ckfinder/userfiles/files/98900387081.pdfIn PDF document text
    • http://akwarella.pl/user_uploads/file/fikesuv.pdfIn PDF document text
    • http://acrclubinversores.com/files/galeria/files/letosazavakax.pdfIn PDF document text
    • http://jiab.net/userData/board/file/fidefam.pdfIn PDF document text
    • http://kartinatv.org/uploads/files/lekap.pdfIn PDF document text
    • https://machinex-machines.com/UserFiles/File/96320884368.pdfIn PDF document text
    • http://urgentcarepb.com/userfiles/file/23784235526.pdfIn PDF document text
    • https://latrinquette.com/upload/editor/file/72615544943.pdfIn PDF document text
    • http://csc020.com/userfiles/file/20210906124326_7uw820.pdfIn PDF document text
    • https://gedayapi.com/userfiles/file/84636010553.pdfIn PDF document text
    • https://simbhaolipower.com/images/file/ralijosopuwevazelesep.pdfIn PDF document text
    • http://aotem.com/data/home/qxu1780220113/htdocs/uploadfile/files/27734096810.pdfIn PDF document text
    • https://yarpaket.ru/userfiles/file/53019061708.pdfIn PDF document text
    • http://spadhotel.com/basefile/spadhotelcom/files/kafojafukerokivaroliviwus.pdfIn PDF document text
    • https://eco-translation.ca/upload/editor/file/95145865950.pdfIn PDF document text
    • https://www.agencesramos.com/ckfinder/userfiles/files/duxoxibobi.pdfIn PDF document text
    • http://decaiyun.com/upload/file/210902065153518871iszbpokluny9.pdfIn PDF document text
    • https://kaemsp.org/upload/editor/file/xadixar.pdfIn PDF document text
    • http://thermogroup.ru/uploads/files/46647785337.pdfIn PDF document text
    • http://nemdanangpho.com/uploads/2021-09-07/images/files/37380332132.pdfIn PDF document text
    • https://sananselmo.com/wysiwygfiles/file/56152493652.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_off0000c045.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC045 17728 bytes
SHA-256: 4a58c320e9a4981d59f9f283aab5fa2c6cf1ced64b1c4c0c170f47bee4573062
font_01_sfnt_off0000ee07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE07 10876 bytes
SHA-256: 1c9c4c558656018e752acb5afd0e20afa2d3e932d3d5121884586372329a349e
font_02_sfnt_off000106e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106E9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1