Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f791eaa3cde0f55…

MALICIOUS

PDF

85.4 KB Created: 2021-03-29 19:29:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 12de6d6498a3650ceaf4ab0d1cdfbffe SHA-1: 16950edc3421215592ce6cc2f45a8ca96c888853 SHA-256: 1f791eaa3cde0f557a68ecb3c944b29bdf023ea2c8b104dd45084c51b39cb23b
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, suggesting a link farm or SEO spam operation. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. No scripts were extracted, but the presence of numerous external URIs points to an attempt to redirect the user to potentially malicious content.

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
  • 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://kuzutuzo.ru/strik?utm_term=calories+in+taco+bell+7+layer+burrito+no+cheese+no+sour+cream PDF link annotation
    • https://wobipogipexiwom.weebly.com/uploads/1/3/1/0/131070125/3e84e97c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4452588/normal_603d077be0bb0.pdfIn PDF document text
    • http://fajufoturesu.sportsontheweb.net/appendix_a_form_for_gate_2020_download.pdfIn PDF document text
    • https://cdn.sqhk.co/pajubopolak/hhhb5jg/losimutak.pdfIn PDF document text
    • https://cdn.sqhk.co/malevevipali/Hhhjfpm/vovosanivakaxatoxe.pdfIn PDF document text
    • https://cdn.sqhk.co/libuzewis/cigiegd/flying_ants_in_house_after_rain.pdfIn PDF document text
    • https://kofulunaj.weebly.com/uploads/1/3/5/3/135320514/5114774.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4490380/normal_60014bac5b718.pdfIn PDF document text
    • https://sopebanodi.weebly.com/uploads/1/3/4/0/134017095/foxef.pdfIn PDF document text
    • https://cdn.sqhk.co/lusajiki/ifghihj/rozanodujekinarilaguze.pdfIn PDF document text
    • http://gejikojaki.scienceontheweb.net/wetuvidovekibezamapatex.pdfIn PDF document text
    • https://pupazugosabi.weebly.com/uploads/1/3/4/8/134868946/044e29.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://315736c7-1030-4200-8d24-05c9f4951019.filesusr.com/ugd/d19ca0_2f004ece7f714c7ab695b6a5174832e5.pdf?index=trueIn PDF document text
    • http://satovimowenijor.myartsonline.com/vocalsynth_2_manual.pdfIn PDF document text
    • http://bogalibamadom.myartsonline.com/93202686749.pdfIn PDF document text
    • http://xotaferuju.myartsonline.com/calendario_escolar_2020_tucuman.pdfIn PDF document text
    • https://5071cc05-3fa2-46b1-b944-d2523ca4b51d.filesusr.com/ugd/62e2c1_ce16692dd0b14a83947dcdb682c018d2.pdf?index=trueIn PDF document text
    • https://61090d85-22e6-4724-b969-52a17785150c.filesusr.com/ugd/952c2e_5e18877c4a7d44d69736f28c8dcf5f3b.pdf?index=trueIn PDF document text
    • https://95a57b4d-a24c-4412-bd87-88f4f885d252.filesusr.com/ugd/011e4b_39ab2b2fc74c411b90a6cbb00c437693.pdf?index=trueIn PDF document text
    • https://88bec3ce-9cdd-4818-a95b-bcf8ac49d1e7.filesusr.com/ugd/72df48_1516d183f7c6416ebff75b50f97200a8.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_off00010c69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C69 5264 bytes
SHA-256: b9f440dd081679fa0ef1938f5a152051a186dd2f070bb15a6683227de9913814
font_01_sfnt_off00011e31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E31 12312 bytes
SHA-256: 3133ff92f99a6b188de5b7b29e607bc1e839237059067aae66cbec3b52a44877