Malicious PDF — malware analysis report

Static analysis result for SHA-256 35780e03e2756d9a…

MALICIOUS

PDF

80.3 KB Created: 2021-04-26 22:02:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 7cd8becd11c4dc36827d915475d3acb1 SHA-1: 7d0e276b19207137d9c394b5858bcea96f019f8b SHA-256: 35780e03e2756d9af617459f98cd2419677ecadf1fead83dee33cb2fdcaaf533
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to external URLs, one of which is on a disposable domain and uses UTM parameters, suggesting a phishing or malware distribution campaign. The document body is heavily obfuscated and contains metadata from wkhtmltopdf, but the primary malicious activity is the embedded links.

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
  • 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://soxebez.ru/strik?utm_term=canon+inkjet+mx700 PDF link annotation
    • https://nibasekugi.weebly.com/uploads/1/3/1/0/131070633/wabamexidomara-burogidasa-jejiwur-lufezirapurej.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4391915/normal_602faa87b0357.pdfIn PDF document text
    • http://wimebenese.getenjoyment.net/anatomy_trains_download.pdfIn PDF document text
    • http://bowuvudofi.scienceontheweb.net/log_antilog_table.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4476133/normal_5fe2b7e0dac2f.pdfIn PDF document text
    • https://tanafojapazikop.weebly.com/uploads/1/3/4/5/134576724/zovipoxeg.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/c10ea532-d720-4d52-a649-e01830a5343d/the_road_to_el_dorado_full_movie_download_in_hindi_filmyzilla.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cdb4442a-c48f-4672-9637-e518f23dcde6/egyptian_hieroglyphics_letter_meanings.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a4be9ddf-a88b-47e7-ad4c-3c77a80fccc7/sheriff_of_nottingham_robin_hood_prince_of_thieves.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8fdf3e91-10ac-4406-8d5a-67718b96fafc/79045130687.pdfIn PDF document text
    • https://3d1db4d0-c196-4dd3-8d5c-bb108cafbd43.filesusr.com/ugd/479e38_403ef1cc46194c89b0dae15f1358add0.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/f17ac0a6-0eea-4d5e-b7fa-239490756c1b/47384989549.pdfIn PDF document text
    • https://065b66ee-25d8-4381-b309-094abc4d823c.filesusr.com/ugd/2703e6_2729e78a9a4c455a92b2ee735178fd9e.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/60cd786a-b862-4f3c-997c-36f934211f3b/38114937602.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3ae81dff-26ba-464d-8659-1fc0b0a9ff98/t_test_statistic_calculator_without_standard_deviation.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/97f50c3b-53fd-40af-b93e-81a3571c58d5/7733348002.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/29e7b95d-696f-4671-ba01-2fed466d3216/60302729166.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ece41ef0-952b-4e5d-ba19-2529e2af5ef7/26906295645.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_off0000fe9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE9E 4860 bytes
SHA-256: a14e8100a27d79f109e82ab5ad18593ffef26d9d0f4cb8f64cd6a0b5c65d92a2
font_01_sfnt_off00010f2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F2A 10928 bytes
SHA-256: 8a4ce50c537607d8689b5a02e0031ac986d9f62b1270178b40c618732291f704