Malicious PDF — malware analysis report

Static analysis result for SHA-256 1bc1f33ba4f0127c…

MALICIOUS

PDF

78.6 KB Created: 2021-05-27 21:51:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 156c6b188349dc038dcdd47f16da1f7b SHA-1: 241840fa886c05a33520e00f4a5f710dc3cd4507 SHA-256: 1bc1f33ba4f0127cecefeb44f094117ae7788b5c73823d2bb3084f599545357f
244 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with several pointing to known malicious redirectors and disposable hosting, indicating a link farm or phishing attempt. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a phishing or malware distribution lure, likely delivered via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://dafemum.ru/123?utm_term=alibaba+egyptian+cotton+sheets In PDF document text
    • https://cdn-cms.f-static.net/uploads/4421629/normal_6055b6f540fa9.pdfIn PDF document text
    • https://buzomuzugagi.weebly.com/uploads/1/3/4/3/134313884/datutigiwubijid.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4468553/normal_601bc24bcbd68.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415739/normal_60691bba47b0e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446490/normal_600e7fe1a10bc.pdfIn PDF document text
    • https://jujoxiro.weebly.com/uploads/1/3/4/8/134875196/0475af54.pdfIn PDF document text
    • https://bopazexujow.weebly.com/uploads/1/3/4/8/134876268/170483.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4488815/normal_60149329a0fbe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4461245/normal_6063113117a9c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370791/normal_6028f0b5a9ed5.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4453327/normal_5fdf2b6d491f5.pdfIn PDF document text
    • https://bigirafu.weebly.com/uploads/1/3/4/4/134494330/lapetivivane.pdfIn PDF document text
    • https://juxepikipoz.weebly.com/uploads/1/3/4/4/134486641/zufurugiwe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4444096/normal_6042c949deaa1.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4475734/normal_5ff8da266581c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4421213/normal_5fd80bba2164c.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/85bf05b5-f778-449f-b64e-b2df8c42740f/how_to_use_a_vivint_thermostat.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ce298935-4a31-4485-b2ca-7fe3feb42881/astrophysics_for_people_in_a_hurry_free.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_off0000e784.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE784 3364 bytes
SHA-256: 047380a3e46587a406f484809fe82954ecb9287f96c7dd06594e3028894c3e1d
font_01_sfnt_off0000f37c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF37C 5328 bytes
SHA-256: 048475743877f796a983d2358782d42e3971091a0ffdf2beb91b35edb1f4f02f
font_02_sfnt_off000105a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105A5 11580 bytes
SHA-256: 18102f296dde52581bb6a2a7aeabb2bf1ae852cb4f877fa23f00d02799b49afb