Malicious PDF — malware analysis report

Static analysis result for SHA-256 3aef9aec3b27553b…

MALICIOUS

PDF

82.4 KB Created: 2021-04-06 01:27:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: e4b18c33a61aae1843f002cc373f2b2e SHA-1: 78045e8db0dcdb03aa5728f4283a75f214c5df17 SHA-256: 3aef9aec3b27553b56d09655075bc172d7c431c0050e64c35d2e07a597d4bd20
186 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, specifically identified as a phishing trojan by ClamAV. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm or phishing campaign. While no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://druttle.ru/strik?utm_term=html5+text+field+numbers+only PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4366647/normal_6010b62756b9e.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4484383/normal_5fdcdf86f0def.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4453328/normal_60508e1e2a7a3.pdfIn PDF document text
    • https://tixanesel.weebly.com/uploads/1/3/4/2/134234664/f3c2604c1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490127/normal_605fa2f93ee3e.pdfIn PDF document text
    • https://gavawujag.weebly.com/uploads/1/3/4/3/134370084/b70c5610e5349.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4474192/normal_5fedc4ac4ae8d.pdfIn PDF document text
    • https://musevurimimurom.weebly.com/uploads/1/3/4/7/134711136/3641942.pdfIn PDF document text
    • https://vadiduriku.weebly.com/uploads/1/3/4/4/134445950/soxum-misovin.pdfIn PDF document text
    • https://gozezitigaja.weebly.com/uploads/1/3/4/3/134340412/3367981.pdfIn PDF document text
    • https://cdn.sqhk.co/guwuweri/5XQ9gLw/make_a_city_idle_tycoon_apk.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387037/normal_60188560b1b7f.pdfIn PDF document text
    • https://nimukitu.weebly.com/uploads/1/3/4/2/134266418/2869147.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4489834/normal_5fed1b026d66a.pdfIn PDF document text
    • https://cdn.sqhk.co/kizulajeli/9lxdO0b/famous_songs_of_the_70s_and_80s.pdfIn PDF document text
    • https://jewutejaj.weebly.com/uploads/1/3/1/0/131070173/58a956.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/75303d95-5905-46e7-9d1b-26b9bf438732/womugidalomepagub.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/620ba832-b68d-405c-a06b-c0ae433d53f7/the_five_dysfunctions_of_a_team_filetype.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b7b5d2a9-fa38-44d3-aa1e-7e0fdafafee0/how_to_calibrate_cobra_29_lx_max.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000efde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFDE 5240 bytes
SHA-256: 95d73b6644faa15704b98d5f53b40f4bd2eadec3f18adbd44146bde4a025948a
font_01_sfnt_off000101ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101AC 10736 bytes
SHA-256: 5a023069fbf13bcd788c64059ef95bd65fdd9ef42236190b483e8bd06710a7d1
font_02_sfnt_off000126ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126AB 16220 bytes
SHA-256: 7d7301e83855c66e27e4993fed898a4e3feed4fbbc7c3507f2d0c421f9d8380d