Malicious PDF — malware analysis report

Static analysis result for SHA-256 27de86528db136ad…

MALICIOUS

PDF

73.3 KB Created: 2021-03-17 21:13:40 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 91645b425d60555936be8d73c9465db5 SHA-1: 27c992f4acebebc794d58426890fc2a1abbc1aaf SHA-256: 27de86528db136adf66497bccc38cf6e8ada5eb437ba67135a4e11ca57ef7644
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many pointing to disposable domains, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are indicative of a malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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 contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://botokaw.ru/strik?utm_term=solving+inequalities+word+problems+worksheet+with+answers PDF link annotation
    • https://mozufutedubido.weebly.com/uploads/1/3/4/5/134503110/xezoko_xigajuku.pdfIn PDF document text
    • https://cdn.sqhk.co/padumaxifop/sViduhf/5263691859.pdfIn PDF document text
    • https://cdn.sqhk.co/fakosopalo/g25Aohe/88574868994.pdfIn PDF document text
    • https://cdn.sqhk.co/pananele/hhhfOge/kofenebogewaxuge.pdfIn PDF document text
    • https://lagizipat.weebly.com/uploads/1/3/2/6/132681030/pokibusuxiwazawobi.pdfIn PDF document text
    • https://gizetaxawu.weebly.com/uploads/1/3/1/8/131871526/e423ccba94e05.pdfIn PDF document text
    • https://cdn.sqhk.co/dijabidasu/cbqhhhf/27746376406.pdfIn PDF document text
    • https://cdn.sqhk.co/vawadawuleja/ieaihhg/katikuwuxenegijelulabako.pdfIn PDF document text
    • https://cdn.sqhk.co/vetedaxuzele/jhhizie/48255028614.pdfIn PDF document text
    • https://venubitolaxi.weebly.com/uploads/1/3/4/3/134372432/zidolotabibigekasa.pdfIn PDF document text
    • https://cdn.sqhk.co/duditizonut/jgfjbDo/nezofelejosafogis.pdfIn PDF document text
    • https://numibogag.weebly.com/uploads/1/3/4/3/134323011/42aeed075.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4394071/normal_604add9e885c9.pdfIn PDF document text
    • https://cdn.sqhk.co/litalile/uhbk7gU/best_landline_phone_answering_machine.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422918/normal_604d1b804deee.pdfIn PDF document text
    • https://cdn.sqhk.co/demarumiju/ih0hbTq/44936136073.pdfIn PDF document text
    • https://cdn.sqhk.co/nilesatu/FNjgifN/twist_hit_app.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/342866fc-f002-48ed-8f63-cd46d8ba030e/what_do_light_bulb_symbols_mean.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/26105342-d033-4530-9072-cd7dda2f0ed4/8073346100.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c5936ad8-42b4-470c-a192-4d78b846398d/can_alexa_be_used_as_external_speaker.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a27e5f3c-dc0e-4000-92d0-3d02eb06b770/gaxuwizajulejazometir.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dc95172e-7c39-46dc-be0d-b05bc0a717e9/jarikivevukosewamewibudej.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d173.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD173 5840 bytes
SHA-256: e062cafd8e2522c2b13fbdb13ad56abb2e7709c1699040de1e544acdadf5579f
font_01_sfnt_off0000e52b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE52B 10496 bytes
SHA-256: 16baa983aae0a441af846015e9d8c09ad900c44fcdb1a9cfcf771f6eb235b051
font_02_sfnt_off00010932.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10932 4324 bytes
SHA-256: ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3