Malicious PDF — malware analysis report

Static analysis result for SHA-256 43514bf2fdd38e38…

MALICIOUS

PDF

80.4 KB Created: 2021-03-24 03:50:06 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: a1a77f2021d960e8b112cfcb8ee1df62 SHA-1: d67d9b94c7ee33a7de41fb740008c0850e2a9d4c SHA-256: 43514bf2fdd38e382a55d0c7c4fef452f02da84958d02798b0ac1a4ae53e39a8
126 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, indicating a link farm or SEO spamming operation. The ML classifier strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the PDF structure and embedded URIs suggest it's designed to redirect users to potentially malicious or ad-filled websites, masquerading as helpful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 5

  • 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://maypoin.ru/strik?utm_term=how+to+start+an+expository+essay+examples PDF link annotation
    • https://cdn.sqhk.co/lixozimiz/7gi3ujf/81100084750.pdfIn PDF document text
    • https://nobasaxekomu.weebly.com/uploads/1/3/5/3/135322761/7694232.pdfIn PDF document text
    • https://ruwizugaxuluba.weebly.com/uploads/1/3/4/7/134759804/2627864.pdfIn PDF document text
    • https://cdn.sqhk.co/kawurefeki/WPihjbF/77676569782.pdfIn PDF document text
    • http://gibelepij.scienceontheweb.net/como_se_hace_un_arroz_integral.pdfIn PDF document text
    • https://zufezegudowoz.weebly.com/uploads/1/3/2/6/132683286/bofazodep.pdfIn PDF document text
    • http://bovewitavivebu.getenjoyment.net/xizigisabalazezevubetujom.pdfIn PDF document text
    • https://baxakazakibabim.weebly.com/uploads/1/3/4/5/134585713/ratikibe.pdfIn PDF document text
    • http://xelibirujegid.mywebcommunity.org/xewixasixumozixedak.pdfIn PDF document text
    • http://aycotoro7.xyz/dell_inspiron_3847_32gb_ramd5khb.pdfIn PDF document text
    • http://dayzcommunity.info/1976251419t1lmt.pdfIn PDF document text
    • https://zobegutibeg.weebly.com/uploads/1/3/4/9/134902349/tekutofekemumop-zomumunupaji.pdfIn PDF document text
    • http://mojenisijita.mywebcommunity.org/how_to_be_a_creative_photographer.pdfIn PDF document text
    • http://gexomafe.mypressonline.com/como_hackear_wii_rvl-001_usa.pdfIn PDF document text
    • http://biweekamnf.com/employee_absent_letter_format6m13i.pdfIn PDF document text
    • https://jeratevi.weebly.com/uploads/1/3/0/7/130774970/vobekukudivuwute.pdfIn PDF document text
    • https://watorixaziju.weebly.com/uploads/1/3/4/5/134586039/zatopepe-fawobimutezix-tezarivuguxo-zevakejalofi.pdfIn PDF document text
    • https://cdn.sqhk.co/vaziworab/haZeIja/47493760617.pdfIn PDF document text
    • http://fb-copyright-help-from.com/skype_terbaru_2019cdqdz.pdfIn PDF document text
    • https://jazejuvo.weebly.com/uploads/1/3/4/4/134439384/84fade.pdfIn PDF document text
    • https://cdn.sqhk.co/janonaset/ibaUhdm/15479125696.pdfIn PDF document text
    • https://cdn.sqhk.co/sexuzoropa/gjgjic0/police_car_sound_ringtone.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/86171e5b-3247-4d0b-94fe-7b7bfdc2a16b/introductory_mathematical_analysis_14th_edition_free_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c44e297e-5c30-4035-8894-6fec91bb5cb3/axial_racing_scx10_ii_2000_jeep_cherokee_rock_crawler_kit.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/08eb145b-7b00-409d-8316-25ac800c1339/tusazibewududiporas.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_off0000fdf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDF8 5188 bytes
SHA-256: 60a9dfa3fee6d263ad4ac0009d7648eaecdb64f3374152e362e90e1ccb14b6c6
font_01_sfnt_off00010fa0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FA0 10608 bytes
SHA-256: bdad31827917cce698fc4be4f12fdf0c70c708e93317cd0d796ae18140faabc3