Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f80cbbbd660122d…

MALICIOUS

PDF

75.8 KB Created: 2021-03-27 20:58:05 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 2d0494661c24a3eacf2bdcbf832e87d0 SHA-1: 052a2c69055979ea7c365616d01ccc67cf90651c SHA-256: 8f80cbbbd660122d71d52660593122c12224bb037ae4a6b40917339bdc9b0e3d
126 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to disposable domains and employing UTM parameters, indicative of a link farm or SEO spam campaign. The ML classifier strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the PDF structure and embedded URIs suggest an attempt to redirect users to potentially harmful content, aligning with spearphishing attachment tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 5

  • 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://nipisod.ru/strik?utm_term=kayla+workout+abs PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4419205/normal_603b24ba695e7.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4487386/normal_5fe1bed1cf11f.pdfIn PDF document text
    • http://perevod24-card2card.site/lobafasovonojubixiv75ei.pdfIn PDF document text
    • https://kekerisasil.weebly.com/uploads/1/3/0/7/130775365/wifasowaxovat.pdfIn PDF document text
    • http://piredvizhnik.com/how_to_stop_hp_printer_printing_test_pageuxpef.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413369/normal_60272796eba86.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4468563/normal_605c67b6a98f2.pdfIn PDF document text
    • https://zezevibowavaki.weebly.com/uploads/1/3/4/8/134854125/jilutejulodirofumen.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485580/normal_600bb5448d4dd.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450516/normal_5fe93fcaccc15.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4494883/normal_5fc6c4fe4a88b.pdfIn PDF document text
    • https://galifejamadex.weebly.com/uploads/1/3/0/8/130814644/1146959.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4412403/normal_5fdc8714150fb.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4454546/normal_60008b691becd.pdfIn PDF document text
    • https://vagapirub.weebly.com/uploads/1/3/4/6/134648019/lutige.pdfIn PDF document text
    • http://axecheat1.xyz/mosubajewakulexewoghbbpd.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379483/normal_6031f9c5bfb73.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450632/normal_5fe85c105c63f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4446633/normal_5ff3a1356f1da.pdfIn PDF document text
    • https://xitupiwe.weebly.com/uploads/1/3/4/4/134489196/tumizijaj.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/68cea542-0725-4b36-a198-71a95b2bb737/flujo_de_materia_energa_e_informacin_ejemplos.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/213d8736-b118-4475-86b4-def7156248b2/tuxaniporubelazapi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3bbad4f3-7101-44b5-8b3d-5789cc6d0a87/vox_tonelab_se_review.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ea6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA6A 5048 bytes
SHA-256: 730d919c6bc28d00fc969f32c91ec5d78fdf2266e4d6d833eb48acb676e50bc1
font_01_sfnt_off0000fbb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBB9 10928 bytes
SHA-256: 9e073371612ba3857fdec78d30fd81d275279adedb6776b0d05c5763ec507841