Malicious PDF — malware analysis report

Static analysis result for SHA-256 514cf1b103bcbd62…

MALICIOUS

PDF

87.8 KB Created: 2021-03-22 16:06:32 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: bf0da497035347a9e6818b4af895161b SHA-1: a130a878ad6d7f87e557c359e9b1e6e948b6c105 SHA-256: 514cf1b103bcbd623f61c86358c70cb6a21b053bdcb0b07467adfc317b5b1426
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a large number of external links, many pointing to other PDF files hosted on various domains, indicating a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for SEO manipulation or to distribute phishing content. The presence of multiple external URIs and the PDF_SEO_LINK_FARM heuristic confirm the link farm behavior.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://seumenha.ru/strik?utm_term=ipod+homepod+mini PDF link annotation
    • https://cdn.sqhk.co/vonezositixi/cURjehe/vugemofepozolejedigo.pdfIn PDF document text
    • https://cdn.sqhk.co/favejofu/jfdeVMb/pofopanefepijeleje.pdfIn PDF document text
    • https://cdn.sqhk.co/sofizagumup/Tjhif2d/best_captions_for_photos_fb.pdfIn PDF document text
    • https://cdn.sqhk.co/velabolo/if62b2s/seed_minecraft_pe_village_2020.pdfIn PDF document text
    • https://rizimajapalikum.weebly.com/uploads/1/3/4/6/134633575/todaxegezakofapigapu.pdfIn PDF document text
    • https://dukopovofozevi.weebly.com/uploads/1/3/5/2/135295758/67038.pdfIn PDF document text
    • https://nuzukozifazo.weebly.com/uploads/1/3/2/6/132682871/f487cbcbc57.pdfIn PDF document text
    • https://cdn.sqhk.co/kezavilageg/dUrjesC/civil_war_battlefields_map_tennessee.pdfIn PDF document text
    • https://xijexarara.weebly.com/uploads/1/3/4/0/134017378/toguz-jemosadenejo.pdfIn PDF document text
    • https://cdn.sqhk.co/raserijene/BS3haja/argentina_football_jersey_2020.pdfIn PDF document text
    • https://cdn.sqhk.co/bexutavukaro/YBheagd/zozipekomoworade.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/viwoxuz/acknowledgement_in_research_template.pdfIn PDF document text
    • https://a4067306-84c0-45ce-9c36-3cbb795fcb37.filesusr.com/ugd/d5b970_c6ae439841d6485291462ccd58649a6a.pdf?index=trueIn PDF document text
    • https://c63ca81c-6df4-4ec3-bc2e-8508f29a6879.filesusr.com/ugd/d48fe3_03d0dc3e76c04252a91c23baf2452bf9.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/polexebuj/wotozotokodigisasam.pdfIn PDF document text
    • https://f4e740b0-69d0-4d5c-a0c7-362dc6b2ad6d.filesusr.com/ugd/0356fc_cca0004ccd1c48578e769dfe71dd0540.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/latufenaw/literary_devices_in_speech_to_the_virginia_convention.pdfIn PDF document text
    • https://6448a590-b571-4b71-a9e4-820b8531b153.filesusr.com/ugd/782be2_b268e2329b46421aa10e8a0c5c3cfaca.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/nunakixuma/refigitogenipisojawa.pdfIn PDF document text
    • https://s3.amazonaws.com/gizonukorad/general_employment_reference_letter_template.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010436.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10436 4620 bytes
SHA-256: 568a3e3506551689a2c7b33f374f735da5ebc173a8990b26d05a1b02bcc61bf9
font_01_sfnt_off000113ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113CA 12100 bytes
SHA-256: 231a43d7bd414130e1b326eabd1386a37c4ff6320d92bc638301cd7bde799b0c
font_02_sfnt_off00013d4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D4D 16060 bytes
SHA-256: 2173a1880e9f774f759393e7d0d28dda91d04d8a3eae6bea41b822770b343b90