Malicious PDF — malware analysis report

Static analysis result for SHA-256 928b4c4f8310a057…

MALICIOUS

PDF

89.8 KB Created: 2021-03-10 01:54:41 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: c6e86b4c21a81a32ee14d8a3cd8158cf SHA-1: c4869af9c6a8bc8d6b638ca192b5e347cfa8daa0 SHA-256: 928b4c4f8310a057833dd9c331d8b522f64594dedb857a11c88e00c92ca9eb4c
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a large number of external links, identified as a link farm. The ClamAV detection and ML classifier strongly indicate maliciousness, with the links likely serving to distribute malware or engage in phishing. The file's structure and numerous external URLs suggest it's part of a campaign to manipulate search engine results or redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • 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://zajinet.ru/wb?keyword=economists%20assume%20that%20firm%20owners%20want%20to%20maximize PDF link annotation
    • https://gunujudota.weebly.com/uploads/1/3/2/3/132303168/kotabufakaf_wusavogoma.pdfIn PDF document text
    • http://pubgmobiie.com/gesamenokajonu6ldw7.pdfIn PDF document text
    • https://tofesozexeraj.weebly.com/uploads/1/3/4/6/134610570/2479cca9c7e8.pdfIn PDF document text
    • https://wawupibinotab.weebly.com/uploads/1/3/4/9/134900246/7881226.pdfIn PDF document text
    • http://gratoraama.website/telugu_movies_hd_mobilexbgr2.pdfIn PDF document text
    • http://cardioactiveufficiale.site/controlled_experiment_practice_worksheet4hmuc.pdfIn PDF document text
    • https://pelimabogex.weebly.com/uploads/1/3/4/6/134685965/vodoxux-togamaf-wakil-sanuditijoluf.pdfIn PDF document text
    • http://idealica-ordina.site/juderunusofomikizc8xth.pdfIn PDF document text
    • https://rokubupudila.weebly.com/uploads/1/3/1/8/131856034/4744d859d9b.pdfIn PDF document text
    • http://urolog.xyz/89142598015ru6ww.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388160/normal_6024f5474a368.pdfIn PDF document text
    • http://barbanapoli.moscow/economia_ecologica_y_politica_ambiental8ku64.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4379846/normal_60095cc97c934.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4496204/normal_5fee6615c8244.pdfIn PDF document text
    • http://moscow-siberian-force.online/the_missing_link_movie_2018_trailers68yd.pdfIn PDF document text
    • https://fenotitejov.weebly.com/uploads/1/3/5/3/135316040/tabalo.pdfIn PDF document text
    • http://mandarins.space/baldi_dies_mod_apk7z8n3.pdfIn PDF document text
    • http://svoytrylend.xyz/resource_capacity_management_template_excele6yb0.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4484370/normal_6001f0bcb1aef.pdfIn PDF document text
    • http://lalashoppen.online/twitter_careers_new_gradkhduj.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4481408/normal_60411cbd762c4.pdfIn PDF document text
    • http://normab-id.com/15671879026lnx0i.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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_off0001220d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1220D 5256 bytes
SHA-256: f7ccd71af21519fa88820ce59a04f08f0dcb0058af79a008fd7eb80c25563f04
font_01_sfnt_off000133e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133E3 10944 bytes
SHA-256: ccf90aa0321ba19abcbf26239acaf6e13355bb8cfbccad6e6114018e5a0ecebc