Malicious PDF — malware analysis report

Static analysis result for SHA-256 277a4f0cdc638c11…

MALICIOUS

PDF

83.8 KB Created: 2021-03-30 12:09:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 4b40ed8159a735f467cf9e80a636eca2 SHA-1: 8800507d0f5431803c7c44323ee3e8c51eb26bc9 SHA-256: 277a4f0cdc638c11eb8c2b0dce82aa0056fe36275494b5460d4b57f01a636106
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 0.9996

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://ponafet.ru/123?utm_term=comparison+of+economic+systems+worksheet PDF link annotation
    • http://mynasert.online/one_of_us_is_lying_character_chartuqhe6.pdfIn PDF document text
    • http://powajaxib.medianewsonline.com/nse_equity_trading_holidays_2020.pdfIn PDF document text
    • https://tobopitoru.weebly.com/uploads/1/3/4/8/134872655/kufuliren.pdfIn PDF document text
    • https://xakowuval.weebly.com/uploads/1/3/5/3/135316831/kumud-kowikabe.pdfIn PDF document text
    • https://zodutobaziji.weebly.com/uploads/1/3/1/4/131408241/koguvifigonoxagexef.pdfIn PDF document text
    • http://prizinsta365.website/ventilator_associated_pneumonia_guidelines_2018vm67g.pdfIn PDF document text
    • http://xuwuvewisin.mypressonline.com/how_to_get_employment_insurance_canada.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/cb80a139-f68e-4f0e-973d-7900f9d12253/raweloxibobabul.pdfIn PDF document text
    • https://39c1d623-eccb-4af0-a86a-15328a2d61f9.filesusr.com/ugd/3cb6cb_bcdac862b7a84f07a92a9f575ac53ab1.pdf?index=trueIn PDF document text
    • https://5b3500e9-40b4-440a-9ada-171ed8bcf4c9.filesusr.com/ugd/7820d0_30242bf51d0f4f87a7f14ed22a4e94f7.pdf?index=trueIn PDF document text
    • https://488c2ff9-9ff4-499e-8f11-525115e20b22.filesusr.com/ugd/8aba0c_f49b34d912814dab8e27edd28c30a8b9.pdf?index=trueIn PDF document text
    • http://faxiruvud.myartsonline.com/79358121499.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ce0ba43f-4bd8-4c32-8434-4a33b24f4835/samsung_galaxy_note_10_manual_network_selection.pdfIn PDF document text
    • https://s3.amazonaws.com/donukadizolin/vesozonujugimepoxiz.pdfIn PDF document text
    • https://s3.amazonaws.com/petikamov/autoantibodies_in_systemic_sclerosis_unanswered_questions.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e6e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6E9 5292 bytes
SHA-256: f432a4971ae3fc110648a282215932abd63085f02a8737b71ed891d29f788220
font_01_sfnt_off0000f8c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8C7 10688 bytes
SHA-256: 6ad5537b01b5f8ec8fc526e45bb67392c139d80e6176deb74cbf7027b6619ea9
font_02_sfnt_off00011d81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D81 16060 bytes
SHA-256: 99ddc6f5858eb134f8024171ebe717cbd02485c31471b921a5021903b5272953
font_03_sfnt_off0001321b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1321B 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34