Malicious PDF — malware analysis report

Static analysis result for SHA-256 4aa751db93b3c3b8…

MALICIOUS

PDF

73.5 KB Created: 2021-06-08 08:49:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: fa6b8100331a151f292542e03a749566 SHA-1: 2366c728318b5cec6a3ee3601cbd101fea4299c2 SHA-256: 4aa751db93b3c3b882f56b1c76662d8e4db022d5ab9a027c4cb84aea2dd20537
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many pointing to disposable hosting, indicating a link farm or SEO manipulation tactic. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://queure.ru/pbw?utm_term=ending+credits+law+and+order PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4496014/normal_6049d48592fab.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4377371/normal_6020a4edc0043.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379974/normal_601e4a174f017.pdfIn PDF document text
    • https://sutikarojujo.weebly.com/uploads/1/3/4/3/134343437/107853.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4412606/normal_5ff064ff95cbb.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4389106/normal_5fcefd39e3cf0.pdfIn PDF document text
    • https://wuzubetimu.weebly.com/uploads/1/3/4/2/134266391/xukan-linixomi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4416810/normal_60545d940fb03.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379959/normal_60bbcfeb49625.pdfIn PDF document text
    • https://moxujudafetofa.weebly.com/uploads/1/3/2/7/132712376/nivoxasanunofolemamu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4530990/normal_606ae9508f733.pdfIn PDF document text
    • https://jimixinig.weebly.com/uploads/1/3/1/1/131164312/fuweneborukakuzi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489722/normal_6044f77c63a69.pdfIn PDF document text
    • https://nogetutiru.weebly.com/uploads/1/3/4/7/134711470/4095492.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4424400/normal_6047d78dd2827.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/0727a564-4517-40e8-8129-4e4e0bc8af6e/ac_sweep_noise_pspice.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/11db29bd-7c23-4577-bbee-08fec4d43885/chicken_invaders_apk_full_version_free_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/aaac9bbd-7979-483c-9dc7-ff4cf89991b7/pmbok_6th_edition_free_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f0dfbf6a-e613-4a33-9c22-ad8940cd8ae6/nuxog.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/92322b91-a6e0-404f-b82d-ebc9713f50e4/what_is_quaternary_structure_of_a_protein.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5a7d50c2-3214-4139-95f3-ca2fa15318b7/40_days_of_mourning_oman.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d95f010a-48b6-46ed-9bc9-cd0d6a562ecd/pekasexigoxe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1b6f1d53-6cc9-472d-9729-de9100c44d4b/libro_de_tecnologia_3_secundaria_con_enfasis_en_informatica.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/98b69559-2c5c-4362-a7ba-06a930258d34/wazewizixetazivu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/480a12b3-8a2a-4f14-95aa-4329953c0b88/how_to_make_knex_gun_that_shoots.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_off0000e1ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1AD 5156 bytes
SHA-256: 0374aee05849cd41f8c10a0ad2da3d6a8e1ad3583e64598ca8184b9367ac5e81
font_01_sfnt_off0000f35c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF35C 10248 bytes
SHA-256: 72583fa1bc25fd0e2ba7c7fc510ae494963d45e1090ddb0ac50948ddafe2b773