Malicious PDF — malware analysis report

Static analysis result for SHA-256 2515a689321a5d1f…

MALICIOUS

PDF

86.9 KB Created: 2021-04-02 02:14:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 55e70750a3660648733eaed6d2464863 SHA-1: 3457fd6c762840023d7e9fd0a1a48755b4a48605 SHA-256: 2515a689321a5d1fbdce5e2fac897745f874122ba1af0ac236a799b95766ab34
126 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, and contains an embedded URL pointing to a suspicious domain. The document body, though heavily obfuscated, suggests a lure related to a free audiobook, which is a common tactic for phishing or malware delivery. The presence of external URIs and a link farm heuristic further supports the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 5

  • 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.
  • 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://ponafet.ru/strik?utm_term=caballo+de+troya+1+audiolibro+completo+gratis PDF link annotation
    • http://tozonofer.iblogger.org/23367889110.pdfIn PDF document text
    • http://nefetenebubuwid.iblogger.org/72729456680.pdfIn PDF document text
    • https://cdn.sqhk.co/naludibeg/hUhghdE/polyatomic_ions_worksheet_with_answers.pdfIn PDF document text
    • https://vopesowe.weebly.com/uploads/1/3/4/6/134638419/tesumoperez_tajuxipifo.pdfIn PDF document text
    • https://cdn.sqhk.co/naludibeg/gzYqNhj/lefovasu.pdfIn PDF document text
    • http://lumobumekola.getenjoyment.net/cateter_venoso_central_cuidados_de_enfermeria.pdfIn PDF document text
    • https://telozigigozato.weebly.com/uploads/1/3/4/3/134310186/gexijezixupi.pdfIn PDF document text
    • http://zuberisuxivaki.scienceontheweb.net/natural_numbers_and_whole_numbers.pdfIn PDF document text
    • https://tepadomuxufebe.weebly.com/uploads/1/3/1/3/131382092/886262.pdfIn PDF document text
    • https://rurinigumiza.weebly.com/uploads/1/3/5/3/135350695/3148122.pdfIn PDF document text
    • https://cdn.sqhk.co/ferorigife/QGDhaWS/zotifigukebekit.pdfIn PDF document text
    • http://repovor.22web.org/jack_reacher_never_go_back_2016_yts.ag_subtitles.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4409244/normal_5fd60e9339d78.pdfIn PDF document text
    • https://varijiligedag.weebly.com/uploads/1/3/1/3/131383591/wadixikovub.pdfIn PDF document text
    • http://tatanip.medianewsonline.com/how_to_program_remote_for_liftmaster_myq.pdfIn PDF document text
    • http://nugawijuxuv.mywebcommunity.org/wordly_wise_3000_book_5_lesson_6_answer_key.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450043/normal_600d0c17cb812.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/63284f1c-b5ca-4a3d-b075-81c83601d895/68189660013.pdfIn PDF document text
    • http://wedalavunobuwe.rf.gd/maxogututa.pdfIn PDF document text
    • http://teluroluxeterez.myartsonline.com/learn_portuguese_free_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c7edc2fa-0f1a-4ac8-9469-a285d5e37adc/41662385266.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e7f1f630-16d3-4ced-aa32-cca4433f1cbe/18605930560.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
    • https://savannah.gnu.org/projects/freefont/In PDF document text
    • http://www.gnu.org/licenses/In PDF document text
    • http://www.gnu.org/copyleft/gpl.htmlIn PDF document text
    • http://scripts.sil.org/OFLIn 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_off0000e876.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE876 6440 bytes
SHA-256: 3d4760ca295192c89086870ebbac49c5a5945404ea6ab57fca452cf2db5f569a
font_01_sfnt_off0000f86a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF86A 5592 bytes
SHA-256: effd07710888a59f781605efee014234051b1cd19a1ec242cb76a48ea4f376bf
font_02_sfnt_off00010b5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B5A 11904 bytes
SHA-256: 269581a3ea9f15d8275dd58b56cc39120ecf431452ee01a22bab9a8d6de06910
font_03_sfnt_off00013237.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13237 17476 bytes
SHA-256: a92262b536b01ab7948cc7afa2481b380576b1c21ee228d0ed7a0bc62eb5e973