Malicious PDF — malware analysis report

Static analysis result for SHA-256 ad12d98eadcbb887…

MALICIOUS

PDF

82.2 KB Created: 2021-06-10 12:53:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 8560f62eb2d0a9afba720566ca617c08 SHA-1: 8c3a21579ce450222a1abedd7c978c7b4c5344c4 SHA-256: ad12d98eadcbb8874a68c77e7e331147d58398af72a731a3ddfa70fb5e9c2f21
186 Risk Score

Malware Insights

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

The PDF contains numerous external links, identified as a link farm, with one URL pointing to a potentially malicious domain ('synerhu.ru'). The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded links suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://synerhu.ru/pbw?utm_term=nova+launcher+apk+cracked PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4376611/normal_60b90f128271f.pdfIn PDF document text
    • https://xasazixasemopib.weebly.com/uploads/1/3/4/3/134306387/tixosewikavituruk.pdfIn PDF document text
    • https://gojaxuwawozupu.weebly.com/uploads/1/3/1/0/131070912/suruje.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4409409/normal_5fec9ab84ee96.pdfIn PDF document text
    • https://dalemugoxopil.weebly.com/uploads/1/3/4/5/134587536/fuwutukuxepu_midegibem.pdfIn PDF document text
    • https://berekiba.weebly.com/uploads/1/3/1/4/131482976/2e397.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451227/normal_5fe6aac3bf903.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486563/normal_605a28c8c98a3.pdfIn PDF document text
    • https://bufogepuvuzi.weebly.com/uploads/1/3/1/3/131381066/fonekezotamav.pdfIn PDF document text
    • https://xowasesulozuvuv.weebly.com/uploads/1/3/5/3/135347394/pevof-dadudirewaxowo-fezugojo-gojakunidazikun.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4463559/normal_60383224d95d4.pdfIn PDF document text
    • https://refedekejevejat.weebly.com/uploads/1/3/4/3/134312363/3824197.pdfIn PDF document text
    • https://vidijizuv.weebly.com/uploads/1/3/0/7/130776341/fc8e27.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4466662/normal_5fc9db1453de7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4383801/normal_6050515eed2a7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413567/normal_5fd2df635e7d3.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
    • http://lijunew.pbworks.com/w/file/fetch/144786663/newoxudokikiva.pdfIn PDF document text
    • http://sakulibur.pbworks.com/w/file/fetch/144696903/ielts_general_training_writing_task_1_sample_with_answer.pdfIn PDF document text
    • http://naxenuve.pbworks.com/f/sales_ledger_control_account_example.pdfIn PDF document text
    • http://puzavofan.pbworks.com/w/file/fetch/144579390/97334617980.pdfIn PDF document text
    • http://gamaxidad.pbworks.com/f/lasafej.pdfIn PDF document text
    • http://kuperuxowix.pbworks.com/f/11003228464.pdfIn PDF document text
    • http://kopixikosibi.pbworks.com/f/how_to_pay_for_electric_car_charging_points.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_off0000f4a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4A9 4832 bytes
SHA-256: a00573fc5bc32f6d5649394a534b2a8ec60b403920d045513e36c88a03ae47fb
font_01_sfnt_off00010508.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10508 11380 bytes
SHA-256: b89ae172b276b5d22f6c0c2ea0a01e2ae7c82150e72a3ba249c1d9f9758e37a7
font_02_sfnt_off00012ba2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BA2 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c