Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ec35bedbf746646…

MALICIOUS

PDF

79.0 KB Created: 2021-09-14 12:02:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 326149ecf00029c9ce9669d8bc4212af SHA-1: 82661fa4f5aaa59387f243143c1a6395781ac53b SHA-256: 4ec35bedbf746646e1675f4f671ae1eab9dde934ae03b7c3c65f5245fa34c5f3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links to external websites, many of which are hosted on disposable domains or compromised CMS uploads, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, and the document body was unreadable, so the rationale is based on the heuristic findings and URL analysis.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://quiltingacademy.net/fckeditor/userfiles/file/kepalad.pdf
    • https://reformedgeneration.com/userfiles/file/sulexezi.pdf
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/16137a55136c91---vefuzexebu.pdf
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/b6b8de2f6f5099bf9b9a4209f014ef2a/nojakalelavuja.pdf
    • https://loyd.rs/images/file/kufuwufivajefusuzotusiw.pdf
    • https://cengilli.com/icerik_images/file/vapipanipetegapeve.pdf
    • https://iwistw.com/upload/files/29808891612.pdf
    • http://seoulsquare.com/userfiles/file/38902683202.pdf
    • http://tion.hu/upload/file/13121948632.pdf
    • http://ping-property.com/user_img/files/99608352121.pdf
    • http://lynxitservices.com/ckfinder/userfiles/files/loluxekolox.pdf
    • http://smarttechsolutionukltd.com/uploaded_files/userfiles/files/7976849814.pdf
    • http://haki.vn/uploads/files/88199152015.pdf
    • https://atlaskvartir.ua/data/uploads/files/91853378611.pdf
    • https://susta.vn/userfiles/file/49707273023.pdf
    • http://shopcloud.cloud/ckfinder/userfiles/files/10048064239.pdf
    • http://a-xian-coat.com/uploads/files/202109041657298909.pdf
    • https://coevent.ru/upload/files/didin.pdf
    • http://studiomarcheluzzo.it/userfiles/files/nabakixifaneze.pdf
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ede8e08993---maluxisigudawok.pdf
    • http://florylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/76748114088.pdf
    • https://bio-obst-und-gemuese.de/userfiles/file/27451225186.pdf
    • https://mancomunidadvaldizarbe.com/userfiles/files/672525726.pdf
    • https://andymullinscommercial.com/home/andy/public_html/ckfinder/userfiles/files/17111932417.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=play+store+download+install+app
    • 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_off0000d298.bin
cebaeb61cea330ab7152ab2eee051df3ca88cc198a5cba3db173f20f5dfc6321
pdf-font-stream PDF embedded font (sfnt) at offset 0xD298 16828 bytes
font_01_sfnt_off0000fe19.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE19 16792 bytes
font_02_sfnt_off00011630.bin
fc9afdc16d4517f9ce2d62f09d7e2740e4806fe66c5da14b1482c55e0fb8cd02
pdf-font-stream PDF embedded font (sfnt) at offset 0x11630 10588 bytes