Malicious PDF — malware analysis report

Static analysis result for SHA-256 71aaa8b262739db6…

MALICIOUS

PDF

85.5 KB Created: 2021-09-18 06:52:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: b8cfac525c6b27615ee0443756417d3e SHA-1: 3b8a6f5b3fa3a8336ef6296f10ac2f29a0911164 SHA-256: 71aaa8b262739db62ad80e76d27cb477f4be467d87f697b3f89df914d71d83b9
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, with high confidence. It contains numerous external URLs, many of which are hosted on disposable domains, suggesting a link farm or phishing lure. The PDF structure and embedded URLs indicate an attempt to redirect users to potentially malicious content, aligning with spearphishing attachment tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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://nomylo.ru/uplcv?utm_term=how+to+use+your+android+phone+on+your+computer PDF link annotation
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16137f9351758d---10550982673.pdfIn PDF document text
    • http://e-junghan.com/userData/board/file/nuxonupalur.pdfIn PDF document text
    • http://www.synagoge-stommeln.de/ckfinder/userfiles/files/56059027711.pdfIn PDF document text
    • http://cheniou.handysociality.com/upload/files/89469708000.pdfIn PDF document text
    • http://liveisagenix.com/ckfinder/userfiles/files/60181838098.pdfIn PDF document text
    • http://jhdjt.com/images/upload/File/dipalesu.pdfIn PDF document text
    • https://widerbet.pl/userfiles/file/tonotowojosevixagizoz.pdfIn PDF document text
    • http://vimar.ua/userfiles/files/repotaxeburepibapi.pdfIn PDF document text
    • http://acelybio.com/upload/files/96458152386.pdfIn PDF document text
    • http://imobilestore.de/userfiles/file/35694285942.pdfIn PDF document text
    • http://antasboru.com/guvennet/resimlerfiles/82568610610.pdfIn PDF document text
    • https://sim2007.com/files/20234962359.pdfIn PDF document text
    • https://bitree.ru/ckfinder/userfiles/files/likigosazivelokaruwuvuwev.pdfIn PDF document text
    • http://minhnguyenvn.com/uploads/userfiles/file/9574240148.pdfIn PDF document text
    • http://iuf.kr/pds_down/files/vevaxotewegavon.pdfIn PDF document text
    • http://pathtojanna.com/userfiles/files/82264240359.pdfIn PDF document text
    • http://ahkkpcm.org/userfiles/xinibuligimumezivumekixi.pdfIn PDF document text
    • http://jamxmpharmatech.com/upload/files/81934491261.pdfIn PDF document text
    • https://zhavezbozi.cz/data/file/50085925299.pdfIn PDF document text
    • http://kameleonhastanc.hu/files/file/26394693898.pdfIn PDF document text
    • http://softwarefactory.nl/images/file/51486680047.pdfIn PDF document text
    • http://www.halpellet.hu/userfiles/files/87914639642.pdfIn PDF document text
    • http://sistarelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/suritumofeko.pdfIn PDF document text
    • http://fence-alarm.com/userfiles/files/xapetipojonela.pdfIn PDF document text
    • https://barcelonacentromedico.es/files/galeria/files/47947202188.pdfIn PDF document text
    • http://dongduong.net/Images_upload/files/wuxorakeras.pdfIn PDF document text
    • http://campfirewtx.org/userfiles/file/sezibodopovevokizutakeze.pdfIn PDF document text
    • http://expertsystemgroup.com/file_media/file_image/file/kikazilafe.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_off0000e7ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7EA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fffc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFFC 17916 bytes
SHA-256: 69915e4d43fdc3204425bfaaa0c227e71ea77b2afd4d4d290b32546d209455d8
font_02_sfnt_off00012eef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12EEF 11024 bytes
SHA-256: d345cfd078391d8c54dad40b8235fa07a5384598734d0f08ca9f7cca3e148618