Malicious PDF — malware analysis report

Static analysis result for SHA-256 e677f0c1d1b8cc71…

MALICIOUS

PDF

68.6 KB Created: 2021-09-25 09:21:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 303970ed6eae4adcbfd32320cf33cf17 SHA-1: 861faa1d6b173808e81906d6d40b972d2eba129d SHA-256: e677f0c1d1b8cc7121d208bd7503a73bbf9fcc570d0f68572a4b449d4bb4e6c8
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a machine learning model and ClamAV, indicating malicious intent. It contains numerous external URIs and is identified as a link farm hosted on disposable domains, suggesting a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and embedded URIs point towards an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • 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 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://archism.ru/uplcv?utm_term=android+best+open+source+apps PDF link annotation
    • http://studiofranzoni.eu/userfiles/files/8020913038.pdfIn PDF document text
    • https://paroles-vives.com/ckfinder/userfiles/files/85174705586.pdfIn PDF document text
    • http://fkjz.cn/upload/files/2021/09/202109240200265650.pdfIn PDF document text
    • https://kocgrafikavukatwebsitesi.demowebsiteleri.com/upload/files/57881846571.pdfIn PDF document text
    • https://b2cexpressdemo.com/userfiles/file/fugikovu.pdfIn PDF document text
    • http://ghibms.com/userfiles/files/sisejizik.pdfIn PDF document text
    • http://maryalo.com/userData/board/file/migebudu.pdfIn PDF document text
    • https://detectagsafety.com/ckfinder/userfiles/files/63459076056.pdfIn PDF document text
    • http://budaors.varosom.hu/userfiles/files/55536652042.pdfIn PDF document text
    • https://wfca-czech.cz/temp/userfiles/files/zilegulutolesujogunoz.pdfIn PDF document text
    • http://villkasz.hu/editor_up/nepuduvusibajarolodabed.pdfIn PDF document text
    • http://americasbestwingsbeltsville.com/uploads/files/75776445302.pdfIn PDF document text
    • http://airholic.com/UpFiles/WebEditorFiles/file/40145710605.pdfIn PDF document text
    • https://himalmanpower.com/ckfinder/userfiles/files/zarenipotut.pdfIn PDF document text
    • http://kleinschadenexperte.de/userfiles/file/3316547474.pdfIn PDF document text
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161422943c2619---83309115206.pdfIn PDF document text
    • http://dienlanhhuubinh.com/upload/files/lemewavetiwebagikelug.pdfIn PDF document text
    • https://sitpchemcieszyn.pl/_sitpchem/file/51570518354.pdfIn PDF document text
    • https://espritgt.com/userfiles/file/dolalezatefotebizolazob.pdfIn PDF document text
    • http://karpatskiles.ru/store/file/wexenubedajaz.pdfIn PDF document text
    • http://santehnika34.ru/images/file/nevedakezilu.pdfIn PDF document text
    • https://www.suep.gr/ckfinder/userfiles/files/mazuvujelezerinuru.pdfIn PDF document text
    • https://www.abandassociates.com/ckfinder/userfiles/files/32318159418.pdfIn PDF document text
    • http://zabbeleecooking.com/ckfinder/userfiles/files/bujuzenobonamezu.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://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_off0000aeae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAEAE 15308 bytes
SHA-256: d94fca79c0fa38f28bcfe2d1214053e6764819854c9e81b8f8b08bca11db2860
font_01_sfnt_off0000d4ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4AC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ecc3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECC3 10684 bytes
SHA-256: 784ed735b50dc3a3c2c1ea39331ddf935cb38b015c3f5bc357c9610586a2272f