Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d3461df70966575…

MALICIOUS

PDF

73.1 KB Created: 2021-03-31 23:13:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: 7fd0fd774a0e659f091d4333e74b2bef SHA-1: 5b22bbecd0a50d7a914787fec793061f4ef25ba5 SHA-256: 3d3461df70966575e4ec27795b07fc7f4e5172ec9fa66835837989267eb387f6
244 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to disposable domains or known malicious redirectors, indicating a link farm used for phishing or malware distribution. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the link farm suggest the document is designed to redirect users to malicious sites, likely for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://yafferge.ru/123?utm_term=free+ppt+templates+for+computer+science In PDF document text
    • http://alluniversity.fun/8151420855512ua.pdfIn PDF document text
    • https://cdn.sqhk.co/wofamofupu/htxhifN/70003025999.pdfIn PDF document text
    • https://vedalamiru.weebly.com/uploads/1/3/0/7/130776143/lokafekido.pdfIn PDF document text
    • https://cdn.sqhk.co/ropimipaf/jM3hahb/roxenobejozilu.pdfIn PDF document text
    • http://arenda-comp.space/how_to_charge_an_apple_mouse_2raby9.pdfIn PDF document text
    • http://vuvuga.xyz/empires_and_puzzles_cheat_sheetvu4xl.pdfIn PDF document text
    • https://cdn.sqhk.co/ribafesupuro/Ujbjghf/how_to_check_your_kplc_bill_on_phone.pdfIn PDF document text
    • https://tunedewujanan.weebly.com/uploads/1/3/5/3/135345761/putavewekijati_gawapaxopujufi_jalan_xuwevijimu.pdfIn PDF document text
    • https://cdn.sqhk.co/norowitidot/hZv0gO5/t_mobile_prepaid_data_recharge.pdfIn PDF document text
    • https://cdn.sqhk.co/tezofugowura/jhiYlie/muterekogokanaliwenum.pdfIn PDF document text
    • http://citimart.online/physical_healthcare_of_mental_health_consumers_guidelines0xtt3.pdfIn PDF document text
    • https://cdn.sqhk.co/daxozazon/4igQDwb/38093699526.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/jovekus/fiat_126_tuning_guide.pdfIn PDF document text
    • https://s3.amazonaws.com/midaguvimabof/how_much_diary_of_a_wimpy_kid_movies_are_there.pdfIn PDF document text
    • https://s3.amazonaws.com/wizuluworafid/81580906334.pdfIn PDF document text
    • https://f62823ea-e863-4eb7-bd7c-e3bac0139ff1.filesusr.com/ugd/8c639a_7395784b8acb4a82b6ee06071b61f616.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/tokatefozude/bafurusofikilojokoje.pdfIn PDF document text
    • https://b8f7bc2e-5f90-466c-a76c-b8215bfdb3ae.filesusr.com/ugd/9717d9_900b994431a4402097d206ded6180560.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/gedexim/jifopobatapuxomej.pdfIn PDF document text
    • https://1a6c606f-1efd-495f-9370-57f425d809fd.filesusr.com/ugd/1be480_4e562c3e77f84fd1b1eadaf4246dcfe9.pdf?index=trueIn 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_off0000e0ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0EF 5116 bytes
SHA-256: e04408442e1421bad0ed79f413c5e992dcc9e52f4cedeebd5ceb194430659765
font_01_sfnt_off0000f243.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF243 10764 bytes
SHA-256: 67d6c65c3392d929cc8b425635869a754c94c88dac1b37211e3f85519d9a178c