Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b83558e2ee4c58d…

MALICIOUS

PDF

78.4 KB Created: 2021-04-18 21:36:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 1c05d38c3c30c3a6506a9fe823ac028b SHA-1: 1cf7559144f5a8e51f39a8d8358c13dfa589982b SHA-256: 1b83558e2ee4c58d5ebadc6ad86ea5db510632be8770ddc3ff79e4408207a9ea
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://xajibur.ru/strik?utm_term=the+filmmaker%2527s+handbook+review PDF link annotation
    • http://detonic-buy.website/emulator_ps1_for_windowsfx87j.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4381536/normal_6060226e2b01d.pdfIn PDF document text
    • https://lugigotaxur.weebly.com/uploads/1/3/0/9/130969655/9843663.pdfIn PDF document text
    • https://nipifofopofeduv.weebly.com/uploads/1/3/4/3/134338269/b9e62a4d23e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4447273/normal_6037983c495a3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4473375/normal_60264e30cfc42.pdfIn PDF document text
    • https://sasurejif.weebly.com/uploads/1/3/5/9/135966776/wokezinuvule.pdfIn PDF document text
    • http://rubeatyshop.xyz/dysarthria_apraxia_treatment_manualsszed4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4383132/normal_60673b5623c00.pdfIn PDF document text
    • http://newyearshop.site/likodamifrly1.pdfIn PDF document text
    • https://gafeziluwer.weebly.com/uploads/1/3/4/3/134310472/zuwirima.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4471711/normal_6023dc0349648.pdfIn PDF document text
    • https://xulijijexam.weebly.com/uploads/1/3/1/4/131453336/nizodefukodawobil.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/c414e4f2-3b9c-4309-ad2e-e39fe115ff1b/class_matters_chapter_3_summary.pdfIn PDF document text
    • https://4ac36a2f-1533-488b-b282-cf34cdace458.filesusr.com/ugd/bcfc12_b83057fa267f4b5eb8d69bfff517e566.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/b761485a-8560-468a-b38a-489d5b302484/feteduwamelemuxujokalava.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ca134656-91fb-4209-a343-565fdda444ca/how_to_write_literature_review_chapter_for_thesis.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3f2ef22d-df54-4695-8aa1-f2a9cf9d104a/mabikebip.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c9dcef6a-9a81-4a8e-afc1-41c6ac3c7513/67271518633.pdfIn PDF document text
    • https://07e0a16e-b77d-475b-b724-88bbaedb347c.filesusr.com/ugd/8e9e2f_bae3db1c70f14efda454e7de580a49be.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/4a9961c9-50c6-4c05-91be-7d1a495d5217/74228858615.pdfIn PDF document text
    • https://b9a4c3d6-4ccf-4d04-9b0f-c2e9c357e15d.filesusr.com/ugd/e5cbe5_78a802e5c5544dd781baa3aacaa5f021.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/c22e57e3-af21-4ee1-9205-cdca2e194d7d/wifovexuzufuk.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3611fe4c-da20-49ac-ba2c-8f0ed70cb160/how_to_turn_on_jam_wireless_speaker.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/888e651d-f7c5-4e51-8796-e164d231a105/70640111916.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c1f0c6d8-ef79-46fc-acfe-4111f2267b13/63586283310.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_off0000f53d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF53D 5484 bytes
SHA-256: 31e3a221e2b3680884e4e3ee2f1c05b3fc73a556a7b0eba3bdfdf8eb15229abd
font_01_sfnt_off000107cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107CF 10828 bytes
SHA-256: bcf19316a597d23f21d071ea58cd6f68ad9dfe3adb144e6b0f388aef5066ce0a