Malicious PDF — malware analysis report

Static analysis result for SHA-256 31b5b03ddc8e879b…

MALICIOUS

PDF

82.0 KB Created: 2021-05-28 07:07:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-14
MD5: c7df5de94c2848b839039256591b905e SHA-1: c86ab889f1aa988a144de532304a48b2a5bced56 SHA-256: 31b5b03ddc8e879b4c5f387c5a9f30baf63bb1a3b2c5489119172d0a437be183
186 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as a link farm, containing numerous external links to disposable hosting sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were directly extracted, the PDF structure and embedded URIs suggest it's designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://resalured.ru/123?utm_term=vidmate+free++for+android+mobile+2017 PDF link annotation
    • https://kofasarafafe.weebly.com/uploads/1/3/5/3/135390193/3074718.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408463/normal_5fe8431fcb7be.pdfIn PDF document text
    • https://xevowuzari.weebly.com/uploads/1/3/1/4/131437308/nitixigopelugofav.pdfIn PDF document text
    • https://zafasasuk.weebly.com/uploads/1/3/4/7/134713251/1014585.pdfIn PDF document text
    • https://motubisirewu.weebly.com/uploads/1/3/4/5/134529252/jevijixizu_xonodanozesuk_xajowoxemek.pdfIn PDF document text
    • https://zoredufuno.weebly.com/uploads/1/3/4/6/134638801/tunodesaz_vizunotes_kusagakalola.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4411702/normal_60004cdc3f564.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4495686/normal_602e43d86e729.pdfIn PDF document text
    • https://xovamiwif.weebly.com/uploads/1/3/4/0/134096018/61b6f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4451018/normal_600988c1ece79.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4427086/normal_606d67c1377fe.pdfIn PDF document text
    • https://jipubegu.weebly.com/uploads/1/3/1/0/131070098/posuj.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4390071/normal_6035372f9789d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368493/normal_5fd9e761a4173.pdfIn PDF document text
    • https://bezodidamivozel.weebly.com/uploads/1/3/2/6/132683328/17c547f9.pdfIn PDF document text
    • https://lasemekesote.weebly.com/uploads/1/3/4/3/134314396/cfea3581620e0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379474/normal_60471377c0af4.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4415046/normal_5ff8819192960.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/dc09cd87-514c-4844-ac16-8c2a9fbe618c/99649769353.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/24ed4b76-562c-422b-8bc7-10fe8933fca2/psalm_23_4-6_meaning.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/be1844ef-5097-414d-8ada-264180f88e4d/bixefilezifufusupipufiga.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4a4396ae-02a1-4862-a143-8ccb3bef97cf/46006189549.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7f4ac3ac-679a-46e1-b428-d332cf90be65/2006_bmw_330i_repair_manual.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_off0000f515.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF515 2996 bytes
SHA-256: fd7ca904a086d7e4d4549ff606d429cf8a246d475548939133b0259e316ca2cc
font_01_sfnt_off0000ffd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFD8 5384 bytes
SHA-256: 0519145dedd1f5f785d5c6a15d2a561cb85a53484c325cb67f389df543f6d9c1
font_02_sfnt_off0001121f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1121F 11988 bytes
SHA-256: ce92a3aa827ff9367d8e76aaaf55322bc67438c73c2e31310a0ebd4401c7ba5f