Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8555f82aa00a58c…

MALICIOUS

PDF

82.5 KB Created: 2021-06-04 11:50:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: c6fc91e82f239c91cb8b0d923f11282b SHA-1: 7138a10230ac0b931ad544cc6b4d89e3584d8c64 SHA-256: c8555f82aa00a58c9794b6aaad23a54e4cd23ee265e13a26b29281640876371d
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 0.9993

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://cructi.ru/pbw?utm_term=puffin+browser+mod+apk PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4366360/normal_60315edad7398.pdfIn PDF document text
    • https://gilitizek.weebly.com/uploads/1/3/4/1/134131368/ff082b29c.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4385010/normal_5fcc5e3514091.pdfIn PDF document text
    • https://fofebaxokawapo.weebly.com/uploads/1/3/7/4/137499404/diduzegutepole.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4453885/normal_5fcf77505c197.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4481522/normal_6066e2fe94635.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366018/normal_5fdbe29d294ba.pdfIn PDF document text
    • https://defireser.weebly.com/uploads/1/3/4/3/134347292/kumerosarebur-komofilu-lakonisikunuwaw-volajiwimageza.pdfIn PDF document text
    • https://biwewijusegi.weebly.com/uploads/1/3/4/5/134586848/6264339.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4488335/normal_6016e441c5ccc.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
    • http://mogulazedub.pbworks.com/f/exercices_figures_de_style_lyce_seconde.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dcfc3c20-e9d1-4595-a924-0a34c3177737/vadanodizelowerar.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a1cb9a68-6782-45e2-95bb-09d7f83c29b4/bulewad.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/81ec1277-1845-473f-9f9d-2085fcd9d624/sarewikemepebabubatevon.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5fb99caa-2136-4a41-bee6-19865c68e311/english_proverbs_with_meanings_and_examples.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cfcbb882-f726-44e0-86c4-8c4336e34f86/57688606129.pdfIn PDF document text
    • http://morabef.pbworks.com/f/how_to_save_as_x-1a_in_photoshop.pdfIn PDF document text
    • http://jutifakukap.pbworks.com/w/file/fetch/144497133/nojunigelajusenekis.pdfIn PDF document text
    • http://pebenuziwi.pbworks.com/f/yaskawa_v1000_fault_codes_h66.pdfIn PDF document text
    • http://nozobitativi.pbworks.com/f/92092002068.pdfIn PDF document text
    • http://padimagofo.pbworks.com/w/file/fetch/144569778/82098869839.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ec54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC54 2996 bytes
SHA-256: a70bf3a6eafbbe4212620a9d073686e980076bb93cec9fada70851fd09f128b2
font_01_sfnt_off0000f716.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF716 5256 bytes
SHA-256: 51b1e410aec1b7d80957bb0f1efad4991795768ad8f8797c74d25c6b088df681
font_02_sfnt_off000108dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108DC 11200 bytes
SHA-256: 049a80ca611b34b772f580dcc62280252833cceeacb3e15704a407b9ed2f289e
font_03_sfnt_off00012e76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E76 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333