Malicious PDF — malware analysis report

Static analysis result for SHA-256 826b87a31fd1b6f1…

MALICIOUS

PDF

84.0 KB Created: 2021-03-19 17:44:10 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-07
MD5: 8b9485361532713483fdb279ed759399 SHA-1: 63746be0000ed7ac89a5214b37db1289ee10b048 SHA-256: 826b87a31fd1b6f14ddf428795565ba4002b31125822ec5aa0c0c5d434e159a4
126 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains an embedded URI pointing to 'nipisod.ru', which is likely a malicious domain used for phishing or distributing further payloads. The PDF structure and embedded content suggest an attempt to disguise malicious activity as a legitimate document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://nipisod.ru/award?keyword=proses+metabolisme+lemak+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4465545/normal_60183d245c4f0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450870/normal_60216e9fb54ae.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4444371/normal_60121acb258d2.pdfIn PDF document text
    • http://zotagur.22web.org/fafarofewakukonajevido.pdfIn PDF document text
    • https://cdn.sqhk.co/tatidukigag/eji7ghy/92697419781.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4448328/normal_5ffda476b2298.pdfIn PDF document text
    • https://cdn.sqhk.co/kufomopinu/ejij4Fj/tes_avis_sim_c_2019.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4482405/normal_5fe08d9351166.pdfIn PDF document text
    • http://kikaxefe.22web.org/29649915662.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387244/normal_603cf1ca215df.pdfIn PDF document text
    • https://cdn.sqhk.co/rewanizotaj/Zzib0ig/57023956483.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448332/normal_600c877cdac75.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448558/normal_604b2578dc3ce.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/a1bce051-1f3b-4f36-b0fa-f1159282aada/resumen_de_cien_aos_de_soledad_de_gabriel_garcia_marquez_por_capitulos.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e06ef3b7-4104-4a12-907c-8a9730b8cecf/bryant_furnace_age.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9692617a-c096-412c-bf58-1ebfad19f35c/fundamentals_of_physics_by_halliday_resnick_walker_free_download.pdfIn PDF document text
    • https://s3.amazonaws.com/kudowo/lagu_arvindo_simatupang_ho_do_pangondian.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1a7c4971-ccbc-4d58-a155-5e97986fc98e/dsc_neo_adding_codes.pdfIn PDF document text
    • http://guvivel.rf.gd/js_regex_cheat_sheet.pdfIn PDF document text
    • http://vevenamefod.epizy.com/zabofeneluza.pdfIn PDF document text
    • http://limixumijegaf.epizy.com/zurolukurakovig.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ea572b63-0b91-4389-91ae-43f64f04cbe2/yamaha_golf_cart_repair_manual_free.pdfIn PDF document text
    • https://s3.amazonaws.com/sulasatevirexo/hp_laserjet_pro_400_mfp_m425dn_manual_espaol.pdfIn PDF document text
    • https://s3.amazonaws.com/guxosa/nirevuvimaxutabozemivu.pdfIn PDF document text
    • https://s3.amazonaws.com/nisiwanolom/ieee_uat_test_plan_template.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010a0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A0B 5392 bytes
SHA-256: 737a211a9bf3a3007dd9905a68344bd9684aae35b6593c390594614fc1d08dab
font_01_sfnt_off00011c3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C3C 11116 bytes
SHA-256: 6bf2e45fbb61c4dfed10ecc122d59d4d264e1a5593c75691e952e737a514c466