Malicious PDF — malware analysis report

Static analysis result for SHA-256 a43ed454d929704d…

MALICIOUS

PDF

70.4 KB Created: 2021-09-28 07:11:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e5cd3e965fc5420de81ad0625d0c7fce SHA-1: 46dad5cb9fd27b475eba6dcae7cd39604c53718c SHA-256: a43ed454d929704d58fca7c0d3476d77a24bbb1cbf40484c72ddacdcf126167d
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the PDF structure and embedded URLs point towards a social engineering attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://opt-russtd.ru/data_center/upload_pictures/file/fusajonuvobase.pdf
    • http://techbis.pl/files/file/35203076683.pdf
    • http://prinsart.ro/uploads/files/36098053608.pdf
    • https://iqrainternationalschool.org/_assets/files/3173193400.pdf
    • http://issaproject.com/app/views/panel/ckfinder/userfiles/files/71844763445.pdf
    • http://qamsar.org/userfiles/files/21262255666.pdf
    • http://evpltravel.com/xv_image/file/55874592162.pdf
    • http://elmiraclassiccountry.com/wp-content/plugins/super-forms/uploads/php/files/236ec3e8116e0987dfb4ece2a18679a3/50063762581.pdf
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/b83oresrk92j61pcaoa3bjm9vq/nutarakitozilole.pdf
    • http://wsm.hk/images/uploadfiles/file/44773640389.pdf
    • http://huspanda.com/data/ckfinder/files/notekixasuwagedurawoboz.pdf
    • http://filtrydokoparek.pl/img/all/48365725090.pdf
    • https://divetechmarine.com/contents/files/jopakerejaneresudazeka.pdf
    • https://limpiezasinasel.com/userfiles/files/wulekolipadajetefodaja.pdf
    • https://jamisonfurnace.ca/userfiles/files/nanob.pdf
    • http://numismatika-nbkpdy.cz/userfiles/file/zawamug.pdf
    • http://ser-buk.com/userfiles/file/13958440939.pdf
    • http://www.synagoge-stommeln.de/ckfinder/userfiles/files/24862720307.pdf
    • http://impressivetravelvietnam.com/upload/files/59085920634.pdf
    • http://www.tempshift.com/app/webroot/files/uploadimagesfile/40000085702.pdf
    • http://sanga.asia/userData/board/file/nezubogilupewesop.pdf
    • http://www.bc-arman.kz/ckfinder/userfiles/files/44828516824.pdf
    • http://masan315.net/board/imagefile/file/5083207591.pdf
    • http://opt-russtd.ru/data_center/upload_pictures/file/39176080926.pdf
    • http://esipro.fr/userfiles/file/filozikobanejevevumibe.pdf
    • https://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/9123e3c1ebdcbdb92d5dd0803913169b/61692793672.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=harry+potter+and+the+sorcerer%27s+stone+movie+online
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b21b.bin
0e9e260db00c2382969279b63b00a844216bc4c8b4e4af9bc03de68585b38af9
pdf-font-stream PDF embedded font (sfnt) at offset 0xB21B 15832 bytes
font_01_sfnt_off0000da00.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDA00 16792 bytes
font_02_sfnt_off0000f217.bin
68334ff75ea0a48861bac775ed5595278af6bf42458bd00bc87c63cf152ee83f
pdf-font-stream PDF embedded font (sfnt) at offset 0xF217 10984 bytes